SecurityvulnsSECURITYVULNS:DOC:24017Microsoft Security Bulletin MS10-038 - Important Vulnerabilities in Microsoft Office Excel Could Allow Remote Code Execution (2027452)
Microsoft Security Bulletin MS10-038 - Important
Vulnerabilities in Microsoft Office Excel Could Allow Remote Code Execution (2027452)
Published: June 08, 2010
Version: 1.0
General Information
Executive Summary
This security update resolves fourteen privately reported vulnerabilities in Microsoft Office. The more severe vulnerabilities could allow remote code execution if a user opens a specially crafted Excel file. An attacker who successfully exploited any of these vulnerabilities could gain the same user rights as the local user. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights.
This security update is rated Important for all supported editions of Microsoft Office Excel 2002, Microsoft Office Excel 2003, Microsoft Office Excel 2007, Microsoft Office 2004 for Mac, and Microsoft Office 2008 for Mac; Open XML File Format Converter for Mac; and all supported versions of Microsoft Office Excel Viewer and Microsoft Office Compatibility Pack. For more information, see the subsection, Affected and Non-Affected Software, in this section.
The update addresses the vulnerabilities by changing the way that Microsoft Office Excel parses specially crafted Excel files and by correcting the way that the Open XML File Format Converter for Mac installs. For more information about the vulnerability, see the Frequently Asked Questions (FAQ) subsection for the specific vulnerability entry under the next section, Vulnerability Information.
Recommendation. Microsoft recommends that customers apply the update at the earliest opportunity.
Known Issues. Microsoft Knowledge Base Article 2027452 documents the currently known issues that customers may experience when installing this security update. The article also documents recommended solutions for these issues. When currently known issues and recommended solutions pertain only to specific releases of this software, this article provides links to further articles.
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Affected and Non-Affected Software
The following software have been tested to determine which versions or editions are affected. Other versions or editions are either past their support life cycle or are not affected. To determine the support life cycle for your software version or edition, visit Microsoft Support Lifecycle.
Affected Software
Office Suite and Other Software Component Maximum Security Impact Aggregate Severity Rating Bulletins Replaced by this Update
Microsoft Office Suites and Components
Microsoft Office XP Service Pack 3
Microsoft Office Excel 2002 Service Pack 3
(KB982299)
Remote Code Execution
Important
MS10-017
Microsoft Office 2003 Service Pack 3
Microsoft Office Excel 2003 Service Pack 3
(KB982133)
Remote Code Execution
Important
MS10-017
2007 Microsoft Office System Service Pack 1 and 2007 Microsoft Office System Service Pack 2
Microsoft Office Excel 2007 Service Pack 1 and Microsoft Office Excel 2007 Service Pack 2[1]
(KB982308)
Remote Code Execution
Important
MS10-017
Microsoft Office for Mac
Microsoft Office 2004 for Mac
(KB2028866)
Not applicable
Remote Code Execution
Important
MS10-017
Microsoft Office 2008 for Mac
(KB2028864)
Not applicable
Remote Code Execution
Important
MS10-017
Open XML File Format Converter for Mac
(KB2078051)
Not applicable
Remote Code Execution
Important
MS10-017
Other Office Software
Microsoft Office Excel Viewer Service Pack 1 and Microsoft Office Excel Viewer Service Pack 2
(KB982333)
Not applicable
Remote Code Execution
Important
MS10-017
Microsoft Office Compatibility Pack for Word, Excel, and PowerPoint 2007 File Formats Service Pack 1 and Microsoft Office Compatibility Pack for Word, Excel, and PowerPoint 2007 File Formats Service Pack 2
(KB982331)
Not applicable
Remote Code Execution
Important
MS10-017
[1]For Microsoft Office Excel 2007 Service Pack 1 and Microsoft Office Excel 2007 Service Pack 2, in addition to security update package KB982308, customers also need to install the security update for Microsoft Office Compatibility Pack for Word, Excel, and PowerPoint 2007 File Formats Service Pack 1 and Microsoft Office Compatibility Pack for Word, Excel, and PowerPoint 2007 File Formats Service Pack 2 (KB982331) to be protected from the vulnerabilities described in this bulletin.
Non-Affected Software
Office and Other Software
Microsoft Office Excel 2010 (32-bit editions)
Microsoft Office Excel 2010 (64-bit editions)
Microsoft Office File Converter Pack
Microsoft Works 8.5
Microsoft Works 9
Microsoft Office SharePoint Server 2007 Service Pack 1 and Microsoft Office SharePoint Server 2007 Service Pack 2 (32-bit editions)
Microsoft Office SharePoint Server 2007 Service Pack 1 and Microsoft Office SharePoint Server 2007 Service Pack 2 (64-bit editions)
Microsoft SharePoint Server 2010
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Frequently Asked Questions (FAQ) Related to This Security Update
Where are the file information details?
Refer to the reference tables in the Security Update Deployment section for the location of the file information details.
What are the known issues that customers may experience when installing this security update?
Microsoft Knowledge Base Article 2027452 documents the currently known issues that customers may experience when they install this security update. The article also documents recommended solutions for these issues.
MS10-036 also describes a vulnerability in Microsoft Office Excel. How does MS10-036 relate to this bulletin (MS10-038)?
The security update packages in MS10-036 for Microsoft Office Excel 2003 (KB982133) and Microsoft Office Excel 2007 (KB982308) also address the vulnerabilities described in this bulletin, MS10-038. Users with Microsoft Office Excel 2003 or Microsoft Office Excel 2007 installed will only need to install these security update packages once. In addition, MS10-036 offers associated Microsoft Office updates (KB982311 or KB982312) which users must also install in order to address the vulnerability described in MS10-036.
Why does this update address several reported security vulnerabilities?
This update contains support for several vulnerabilities because the modifications that are required to address these issues are located in related files. Instead of having to install several updates that are almost the same, customers need to install this update only.
Does this update contain any non-security related changes to functionality?
Yes, the update package for Microsoft Office Excel 2007 Service Pack 1 and Microsoft Office Excel 2007 Service Pack 2 (KB982308) includes the changes to Excel 2007 described in Microsoft Knowledge Base Article 981046.
What components of the Microsoft Office Compatibility Pack for Word, Excel, and PowerPoint 2007 File Formats are updated by this bulletin?
The update included with this security bulletin applies only to the specific component within the Microsoft Office Compatibility Pack for Word, Excel, and PowerPoint 2007 File Formats that is affected. For example, in an Excel bulletin, only the Excel compatibility pack component files are included in the update packages and not Word or PowerPoint compatibility pack component files. Word compatibility pack component files are updated in a Word bulletin and PowerPoint compatibility pack component files are updated in a PowerPoint bulletin.
What is the Microsoft Office Excel Viewer?
The Microsoft Office Excel Viewer is a replacement for all previous Excel Viewer versions, including Excel Viewer 97 and Excel Viewer 2003. With Excel Viewer, you can open, view, and print Excel workbooks, even if you don't have Excel installed. You can also copy data from Excel Viewer to another program. However, you cannot edit data, save a workbook, or create a new workbook.
I use the 2007 Microsoft Office System Service Pack 1. Are any additional security features included in this update?
Yes, as part of the servicing model for the 2007 Microsoft Office System, when users of Microsoft Office 2007 Service Pack 1 install this update, their systems will be upgraded to security functionality that was initially released with Microsoft Office 2007 Service Pack 2. All updates released after April 24, 2009 for Microsoft Office 2007 will include these security features, which were introduced in the 2007 Microsoft Office System Service Pack 2. We have thoroughly tested this update, but as with all updates, we recommend that users perform testing appropriate to the environment and configuration of their systems.
The Office component discussed in this article is part of the Office Suite that I have installed on my system; however, I did not choose to install this specific component. Will I be offered this update?
Yes, if the version of the Office Suite installed on your system was delivered with the component discussed in this bulletin, the system will be offered updates for it whether the component is installed or not. The detection logic used to scan for affected systems is designed to check for updates for all components that shipped with the particular Office Suite and offer the updates to a system. Users who choose not to apply an update for a component that is not installed, but is included in their version of the Office Suite, will not increase the security risk of that system. On the other hand, users who do choose to install the update will not have a negative impact on the security or performance of a system.
Does the offer to update a non-vulnerable version of Microsoft Office constitute an issue in the Microsoft update mechanism?
No, the update mechanism is functioning correctly in that it detects a lower version of the files on the system than in the update package and thus, offers the update.
Why is this update only Important for all affected versions of Excel?
Microsoft Office Excel 2002 and later versions have a built-in feature that prompts a user to Open, Save, or Cancel before opening a document. This mitigating factor reduces the vulnerability from Critical to Important because the vulnerability requires more than a single user action to complete the exploit.
I am using an older release of the software discussed in this security bulletin. What should I do?
The affected software listed in this bulletin have been tested to determine which releases are affected. Other releases are past their support life cycle. For more information about the product lifecycle, visit the Microsoft Support Lifecycle Web site.
It should be a priority for customers who have older releases of the software to migrate to supported releases to prevent potential exposure to vulnerabilities. To determine the support lifecycle for your software release, see Select a Product for Lifecycle Information. For more information about service packs for these software releases, see Lifecycle Supported Service Packs.
Customers who require custom support for older software must contact their Microsoft account team representative, their Technical Account Manager, or the appropriate Microsoft partner representative for custom support options. Customers without an Alliance, Premier, or Authorized Contract can contact their local Microsoft sales office. For contact information, visit the Microsoft Worldwide Information Web site, select the country in the Contact Information list, and then click Go to see a list of telephone numbers. When you call, ask to speak with the local Premier Support sales manager. For more information, see the Microsoft Support Lifecycle Policy FAQ.
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Vulnerability Information
Severity Ratings and Vulnerability Identifiers
The following severity ratings assume the potential maximum impact of the vulnerability. For information regarding the likelihood, within 30 days of this security bulletin's release, of the exploitability of the vulnerability in relation to its severity rating and security impact, please see the Exploitability Index in the June bulletin summary. For more information, see Microsoft Exploitability Index.
Vulnerability Severity Rating and Maximum Security Impact by Affected Software
Affected Software Excel Record Parsing Memory Corruption Vulnerability - CVE-2010-0821 Excel Object Stack Overflow Vulnerability - CVE-2010-0822 Excel Memory Corruption Vulnerability - CVE-2010-0823 Excel Record Memory Corruption Vulnerability - CVE-2010-0824 Excel Record Memory Corruption Vulnerability - CVE-2010-1245 Excel RTD Memory Corruption Vulnerability - CVE-2010-1246 Excel Memory Corruption Vulnerability - CVE-2010-1247 Excel HFPicture Memory Corruption Vulnerability - CVE-2010-1248 Excel Memory Corruption Vulnerability - CVE-2010-1249 Excel EDG Memory Corruption Vulnerability - CVE-2010-1250 Excel Record Stack Corruption Vulnerability - CVE-2010-1251 Excel String Variable Vulnerability - CVE-2010-1252 Excel ADO Object Vulnerability - CVE-2010-1253 Mac Office Open XML Permissions Vulnerability - CVE-2010-1254 Aggregate Severity Rating
Microsoft Office Suites and Components
Microsoft Office Excel 2002 Service Pack 3
Important
Remote Code Execution
Important
Remote Code Execution
Important
Remote Code Execution
Important
Remote Code Execution
Important
Remote Code Execution
Important
Remote Code Execution
Important
Remote Code Execution
Important
Remote Code Execution
Important
Remote Code Execution
Important
Remote Code Execution
Important
Remote Code Execution
Important
Remote Code Execution
Important
Remote Code Execution
Not applicable
Important
Microsoft Office Excel 2003 Service Pack 3
Important
Remote Code Execution
Not applicable
Important
Remote Code Execution
Not applicable
Not applicable
Not applicable
Not applicable
Not applicable
Not applicable
Not applicable
Not applicable
Not applicable
Not applicable
Not applicable
Important
Microsoft Office Excel 2007 Service Pack 1
Important
Remote Code Execution
Not applicable
Important
Remote Code Execution
Not applicable
Not applicable
Not applicable
Not applicable
Not applicable
Not applicable
Not applicable
Not applicable
Not applicable
Important
Remote Code Execution
Not applicable
Important
Microsoft Office Excel 2007 Service Pack 2
Important
Remote Code Execution
Not applicable
Important
Remote Code Execution
Not applicable
Not applicable
Not applicable
Not applicable
Not applicable
Not applicable
Not applicable
Not applicable
Not applicable
Important
Remote Code Execution
Not applicable
Important
Microsoft Office for Mac
Microsoft Office 2004 for Mac
Important
Remote Code Execution
Important
Remote Code Execution
Important
Remote Code Execution
Important
Remote Code Execution
Important
Remote Code Execution
Not applicable
Not applicable
Important
Remote Code Execution
Important
Remote Code Execution
Important
Remote Code Execution
Important
Remote Code Execution
Important
Remote Code Execution
Important
Remote Code Execution
Not applicable
Important
Microsoft Office 2008 for Mac
Important
Remote Code Execution
Important
Remote Code Execution
Important
Remote Code Execution
Not applicable
Important
Remote Code Execution
Not applicable
Not applicable
Not applicable
Important
Remote Code Execution
Important
Remote Code Execution
Not applicable
Not applicable
Important
Remote Code Execution
Not applicable
Important
Open XML File Format Converter for Mac
Important
Remote Code Execution
Important
Remote Code Execution
Important
Remote Code Execution
Not applicable
Important
Remote Code Execution
Not applicable
Not applicable
Not applicable
Important
Remote Code Execution
Important
Remote Code Execution
Not applicable
Not applicable
Important
Remote Code Execution
Important
Elevation of Privilege
Important
Other Office Software
Microsoft Office Excel Viewer Service Pack 1 and Microsoft Office Excel Viewer Service Pack 2
Important
Remote Code Execution
Not applicable
Important
Remote Code Execution
Not applicable
Not applicable
Not applicable
Not applicable
Not applicable
Not applicable
Not applicable
Not applicable
Not applicable
Not applicable
Not applicable
Important
Microsoft Office Compatibility Pack for Word, Excel, and PowerPoint 2007 File Formats Service Pack 1 and Microsoft Office Compatibility Pack for Word, Excel, and PowerPoint 2007 File Formats Service Pack 2
Important
Remote Code Execution
Not applicable
Important
Remote Code Execution
Not applicable
Not applicable
Not applicable
Not applicable
Not applicable
Not applicable
Not applicable
Not applicable
Not applicable
Important
Remote Code Execution
Not applicable
Important
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Excel Record Parsing Memory Corruption Vulnerability - CVE-2010-0821
A remote code execution vulnerability exists in the way that Microsoft Office Excel handles specially crafted Excel files. An attacker who successfully exploited this vulnerability could take complete control of an affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights.
To view this vulnerability as a standard entry in the Common Vulnerabilities and Exposures list, see CVE-2010-0821.
Mitigating Factors for Excel Record Parsing Memory Corruption Vulnerability - CVE-2010-0821
Mitigation refers to a setting, common configuration, or general best-practice, existing in a default state, that could reduce the severity of exploitation of a vulnerability. The following mitigating factors may be helpful in your situation:
•
An attacker who successfully exploited this vulnerability could gain the same user rights as the local user. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights.
•
In a Web-based attack scenario, an attacker could host a Web site that contains a Web page that is used to exploit this vulnerability. In addition, compromised Web sites and Web sites that accept or host user-provided content or advertisements could contain specially crafted content that could exploit this vulnerability. In all cases, however, an attacker would have no way to force users to visit these Web sites. Instead, an attacker would have to convince users to visit the Web site, typically by getting them to click a link in an e-mail message or Instant Messenger message that takes users to the attacker’s Web site, and then convince them to open the specially crafted Excel file.
•
The vulnerability cannot be exploited automatically through e-mail. For an attack to be successful a user must open an attachment that is sent in an e-mail message.
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Workarounds for Excel Record Parsing Memory Corruption Vulnerability - CVE-2010-0821
Workaround refers to a setting or configuration change that does not correct the underlying vulnerability but would help block known attack vectors before you apply the update. Microsoft has tested the following workarounds and states in the discussion whether a workaround reduces functionality:
•
Use Microsoft Office File Block policy to block the opening of Office 2003 and earlier documents from unknown or untrusted sources and locations
The following registry scripts can be used to set the File Block policy.
Note Modifying the Registry incorrectly can cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that problems resulting from incorrect modification of the Registry can be solved. Modify the Registry at your own risk.
•
For Office 2003
Windows Registry Editor Version 5.00
[HKEY_CURRENT_USER\Software\Microsoft\Office\11.0\Excel\Security\FileOpenBlock]
"BinaryFiles"=dword:00000001
Note In order to use 'FileOpenBlock' with Microsoft Office 2003, all of the latest security updates for Microsoft Office 2003 must be applied.
•
For 2007 Office system
Windows Registry Editor Version 5.00
[HKEY_CURRENT_USER\Software\Policies\Microsoft\Office\12.0\Excel\Security\FileOpenBlock]
"BinaryFiles"=dword:00000001
Note In order to use 'FileOpenBlock' with the 2007 Microsoft Office system, all of the latest security updates for the 2007 Microsoft Office system must be applied.
Impact of workaround. Users who have configured the File Block policy and have not configured a special "exempt directory" as discussed in Microsoft Knowledge Base Article 922848 will be unable to open Office 2003 files or earlier versions in Office 2003 or 2007 Microsoft Office System.
How to undo the workaround:
•
For Office 2003
Windows Registry Editor Version 5.00
[HKEY_CURRENT_USER\Software\Microsoft\Office\11.0\Excel\Security\FileOpenBlock]
"BinaryFiles"=dword:00000000
•
For 2007 Office system
Windows Registry Editor Version 5.00
[HKEY_CURRENT_USER\Software\Policies\Microsoft\Office\12.0\Excel\Security\FileOpenBlock]
"BinaryFiles"=dword:00000000
•
Use the Microsoft Office Isolated Conversion Environment (MOICE) when opening files from unknown or untrusted sources
The Microsoft Office Isolated Conversion Environment (MOICE) helps protect Office 2003 installations by more securely opening Word, Excel, and PowerPoint binary format files.
To install MOICE, you must have Office 2003 or 2007 Office system installed.
To install MOICE, you must have the Compatibility Pack for Word, Excel, and PowerPoint 2007 File Formats. The compatibility pack is available as a free download from the Microsoft Download Center:
Download the FileFormatConverters.exe package now
MOICE requires all updates that are recommended for all Office programs. Visit Microsoft Update to install all recommended updates:
http://update.microsoft.com/microsoftupdate/v6/default.aspx?ln=en-us
For Excel
To enable MOICE, change the registered handler for the .xls, .xlt, and .xla file formats. The following table describes the command to enable or to disable MOICE for the .xls, .xlt, and .xla file formats:
Command to enable MOICE to be the registered handler Command to disable MOICE as the registered handler
ASSOC .XLS=oice.excel.sheet
ASSOC .xls=Excel.Sheet.8
ASSOC .XLT=oice.excel.template
ASSOC .xlt=Excel.Template
ASSOC .XLA=oice.excel.addin
ASSOC .xla=Excel.Addin
Note On Windows Vista, Windows Server 2008, Windows 7, and Windows Server 2008 R2, the commands above will need to be run from an elevated command prompt.
For more information on MOICE, see Microsoft Knowledge Base Article 935865.
Impact of workaround. Office 2003 and earlier formatted documents that are converted to the 2007 Microsoft Office System Open XML format by MOICE will not retain macro functionality. Additionally, documents with passwords or that are protected with Digital Rights Management cannot be converted.
•
Do not open Excel files that you receive from untrusted sources or that you receive unexpectedly from trusted sources. This vulnerability could be exploited when a user opens a specially crafted file.
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FAQ for Excel Record Parsing Memory Corruption Vulnerability - CVE-2010-0821
What is the scope of the vulnerability?
This is a remote code execution vulnerability. An attacker who successfully exploited this vulnerability could take complete control of an affected system remotely. An attacker could then install programs or view, change, or delete data; or create new accounts with full user rights.
What causes the vulnerability?
The vulnerability exists because of the way that Microsoft Office Excel parses the Excel file format when opening a specially crafted Excel file.
What might an attacker use the vulnerability to do?
An attacker who successfully exploited this vulnerability could run arbitrary code as the logged-on user. If a user is logged on with administrative user rights, an attacker could take complete control of the affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights.
How could an attacker exploit the vulnerability?
Exploitation of this vulnerability requires that a user open a specially crafted Excel file with an affected version of Microsoft Office Excel.
In an e-mail attack scenario, an attacker could exploit the vulnerability by sending a specially crafted Excel file to the user and by convincing the user to open the file.
In a Web-based attack scenario, an attacker would have to host a Web site that contains an Excel file that is used to attempt to exploit this vulnerability. In addition, compromised Web sites and Web sites that accept or host user-provided content could contain specially crafted content that could exploit this vulnerability. An attacker would have no way to force users to visit a specially crafted Web site. Instead, an attacker would have to convince them to visit the Web site, typically by getting them to click a link that takes them to the attacker's site, and then convince them to open the specially crafted Excel file.
What systems are primarily at risk from the vulnerability?
Systems where Microsoft Office Excel is used, including workstations and terminal servers, are primarily at risk. Servers could be at more risk if administrators allow users to log on to servers and to run programs. However, best practices strongly discourage allowing this.
What does the update do?
This update addresses the vulnerability by changing the way that Microsoft Office Excel parses specially crafted Excel files.
When this security bulletin was issued, had this vulnerability been publicly disclosed?
No. Microsoft received information about this vulnerability through responsible disclosure.
When this security bulletin was issued, had Microsoft received any reports that this vulnerability was being exploited?
No. Microsoft had not received any information to indicate that this vulnerability had been publicly used to attack customers when this security bulletin was originally issued.
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Excel Object Stack Overflow Vulnerability - CVE-2010-0822
A remote code execution vulnerability exists in the way that Microsoft Office Excel handles specially crafted Excel files. An attacker who successfully exploited this vulnerability could take complete control of an affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights.
To view this vulnerability as a standard entry in the Common Vulnerabilities and Exposures list, see CVE-2010-0822.
Mitigating Factors for Excel Object Stack Overflow Vulnerability - CVE-2010-0822
Mitigation refers to a setting, common configuration, or general best-practice, existing in a default state, that could reduce the severity of exploitation of a vulnerability. The following mitigating factors may be helpful in your situation:
•
An attacker who successfully exploited this vulnerability could gain the same user rights as the local user. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights.
•
In a Web-based attack scenario, an attacker could host a Web site that contains a Web page that is used to exploit this vulnerability. In addition, compromised Web sites and Web sites that accept or host user-provided content or advertisements could contain specially crafted content that could exploit this vulnerability. In all cases, however, an attacker would have no way to force users to visit these Web sites. Instead, an attacker would have to convince users to visit the Web site, typically by getting them to click a link in an e-mail message or Instant Messenger message that takes users to the attacker’s Web site, and then convince them to open the specially crafted Excel file.
•
The vulnerability cannot be exploited automatically through e-mail. For an attack to be successful a user must open an attachment that is sent in an e-mail message.
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Workarounds for Excel Object Stack Overflow Vulnerability - CVE-2010-0822
Workaround refers to a setting or configuration change that does not correct the underlying vulnerability but would help block known attack vectors before you apply the update. Microsoft has tested the following workarounds and states in the discussion whether a workaround reduces functionality:
•
Do not open Excel files that you receive from untrusted sources or that you receive unexpectedly from trusted sources. This vulnerability could be exploited when a user opens a specially crafted file.
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FAQ for Excel Object Stack Overflow Vulnerability - CVE-2010-0822
What is the scope of the vulnerability?
This is a remote code execution vulnerability. An attacker who successfully exploited this vulnerability could take complete control of an affected system remotely. An attacker could then install programs or view, change, or delete data; or create new accounts with full user rights.
What causes the vulnerability?
The vulnerability exists because of the way that Microsoft Office Excel parses the Excel file format when opening a specially crafted Excel file.
What might an attacker use the vulnerability to do?
An attacker who successfully exploited this vulnerability could run arbitrary code as the logged-on user. If a user is logged on with administrative user rights, an attacker could take complete control of the affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights.
How could an attacker exploit the vulnerability?
Exploitation of this vulnerability requires that a user open a specially crafted Excel file with an affected version of Microsoft Office Excel.
In an e-mail attack scenario, an attacker could exploit the vulnerability by sending a specially crafted Excel file to the user and by convincing the user to open the file.
In a Web-based attack scenario, an attacker would have to host a Web site that contains an Excel file that is used to attempt to exploit this vulnerability. In addition, compromised Web sites and Web sites that accept or host user-provided content could contain specially crafted content that could exploit this vulnerability. An attacker would have no way to force users to visit a specially crafted Web site. Instead, an attacker would have to convince them to visit the Web site, typically by getting them to click a link that takes them to the attacker's site, and then convince them to open the specially crafted Excel file.
What systems are primarily at risk from the vulnerability?
Systems where Microsoft Office Excel is used, including workstations and terminal servers, are primarily at risk. Servers could be at more risk if administrators allow users to log on to servers and to run programs. However, best practices strongly discourage allowing this.
What does the update do?
This update addresses the vulnerability by changing the way that Microsoft Office Excel parses specially crafted Excel files.
When this security bulletin was issued, had this vulnerability been publicly disclosed?
No. Microsoft received information about this vulnerability through responsible disclosure.
When this security bulletin was issued, had Microsoft received any reports that this vulnerability was being exploited?
No. Microsoft had not received any information to indicate that this vulnerability had been publicly used to attack customers when this security bulletin was originally issued.
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Excel Memory Corruption Vulnerability - CVE-2010-0823
A remote code execution vulnerability exists in the way that Microsoft Office Excel handles specially crafted Excel files. An attacker who successfully exploited this vulnerability could take complete control of an affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights.
To view this vulnerability as a standard entry in the Common Vulnerabilities and Exposures list, see CVE-2010-0823.
Mitigating Factors for Excel Memory Corruption Vulnerability - CVE-2010-0823
Mitigation refers to a setting, common configuration, or general best-practice, existing in a default state, that could reduce the severity of exploitation of a vulnerability. The following mitigating factors may be helpful in your situation:
•
An attacker who successfully exploited this vulnerability could gain the same user rights as the local user. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights.
•
In a Web-based attack scenario, an attacker could host a Web site that contains a Web page that is used to exploit this vulnerability. In addition, compromised Web sites and Web sites that accept or host user-provided content or advertisements could contain specially crafted content that could exploit this vulnerability. In all cases, however, an attacker would have no way to force users to visit these Web sites. Instead, an attacker would have to convince users to visit the Web site, typically by getting them to click a link in an e-mail message or Instant Messenger message that takes users to the attacker’s Web site, and then convince them to open the specially crafted Excel file.
•
The vulnerability cannot be exploited automatically through e-mail. For an attack to be successful a user must open an attachment that is sent in an e-mail message.
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Workarounds for Excel Memory Corruption Vulnerability - CVE-2010-0823
Workaround refers to a setting or configuration change that does not correct the underlying vulnerability but would help block known attack vectors before you apply the update. Microsoft has tested the following workarounds and states in the discussion whether a workaround reduces functionality:
•
Use Microsoft Office File Block policy to block the opening of Office 2003 and earlier documents from unknown or untrusted sources and locations
The following registry scripts can be used to set the File Block policy.
Note Modifying the Registry incorrectly can cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that problems resulting from incorrect modification of the Registry can be solved. Modify the Registry at your own risk.
•
For Office 2003
Windows Registry Editor Version 5.00
[HKEY_CURRENT_USER\Software\Microsoft\Office\11.0\Excel\Security\FileOpenBlock]
"BinaryFiles"=dword:00000001
Note In order to use 'FileOpenBlock' with Microsoft Office 2003, all of the latest security updates for Microsoft Office 2003 must be applied.
•
For 2007 Office system
Windows Registry Editor Version 5.00
[HKEY_CURRENT_USER\Software\Policies\Microsoft\Office\12.0\Excel\Security\FileOpenBlock]
"BinaryFiles"=dword:00000001
Note In order to use 'FileOpenBlock' with the 2007 Microsoft Office system, all of the latest security updates for the 2007 Microsoft Office system must be applied.
Impact of workaround. Users who have configured the File Block policy and have not configured a special "exempt directory" as discussed in Microsoft Knowledge Base Article 922848 will be unable to open Office 2003 files or earlier versions in Office 2003 or 2007 Microsoft Office System.
How to undo the workaround:
•
For Office 2003
Windows Registry Editor Version 5.00
[HKEY_CURRENT_USER\Software\Microsoft\Office\11.0\Excel\Security\FileOpenBlock]
"BinaryFiles"=dword:00000000
•
For 2007 Office system
Windows Registry Editor Version 5.00
[HKEY_CURRENT_USER\Software\Policies\Microsoft\Office\12.0\Excel\Security\FileOpenBlock]
"BinaryFiles"=dword:00000000
•
Use the Microsoft Office Isolated Conversion Environment (MOICE) when opening files from unknown or untrusted sources
The Microsoft Office Isolated Conversion Environment (MOICE) helps protect Office 2003 installations by more securely opening Word, Excel, and PowerPoint binary format files.
To install MOICE, you must have Office 2003 or 2007 Office system installed.
To install MOICE, you must have the Compatibility Pack for Word, Excel, and PowerPoint 2007 File Formats. The compatibility pack is available as a free download from the Microsoft Download Center:
Download the FileFormatConverters.exe package now
MOICE requires all updates that are recommended for all Office programs. Visit Microsoft Update to install all recommended updates:
http://update.microsoft.com/microsoftupdate/v6/default.aspx?ln=en-us
For Excel
To enable MOICE, change the registered handler for the .xls, .xlt, and .xla file formats. The following table describes the command to enable or to disable MOICE for the .xls, .xlt, and .xla file formats:
Command to enable MOICE to be the registered handler Command to disable MOICE as the registered handler
ASSOC .XLS=oice.excel.sheet
ASSOC .xls=Excel.Sheet.8
ASSOC .XLT=oice.excel.template
ASSOC .xlt=Excel.Template
ASSOC .XLA=oice.excel.addin
ASSOC .xla=Excel.Addin
Note On Windows Vista, Windows Server 2008, Windows 7, and Windows Server 2008 R2, the commands above will need to be run from an elevated command prompt.
For more information on MOICE, see Microsoft Knowledge Base Article 935865.
Impact of workaround. Office 2003 and earlier formatted documents that are converted to the 2007 Microsoft Office System Open XML format by MOICE will not retain macro functionality. Additionally, documents with passwords or that are protected with Digital Rights Management cannot be converted.
•
Do not open Excel files that you receive from untrusted sources or that you receive unexpectedly from trusted sources. This vulnerability could be exploited when a user opens a specially crafted file.
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FAQ for Excel Memory Corruption Vulnerability - CVE-2010-0823
What is the scope of the vulnerability?
This is a remote code execution vulnerability. An attacker who successfully exploited this vulnerability could take complete control of an affected system remotely. An attacker could then install programs or view, change, or delete data; or create new accounts with full user rights.
What causes the vulnerability?
The vulnerability exists because of the way that Microsoft Office Excel parses malformed chart sheet substreams in the Excel file format when opening a specially crafted Excel file.
What might an attacker use the vulnerability to do?
An attacker who successfully exploited this vulnerability could run arbitrary code as the logged-on user. If a user is logged on with administrative user rights, an attacker could take complete control of the affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights.
How could an attacker exploit the vulnerability?
Exploitation of this vulnerability requires that a user open a specially crafted Excel file with an affected version of Microsoft Office Excel.
In an e-mail attack scenario, an attacker could exploit the vulnerability by sending a specially crafted Excel file to the user and by convincing the user to open the file.
In a Web-based attack scenario, an attacker would have to host a Web site that contains an Excel file that is used to attempt to exploit this vulnerability. In addition, compromised Web sites and Web sites that accept or host user-provided content could contain specially crafted content that could exploit this vulnerability. An attacker would have no way to force users to visit a specially crafted Web site. Instead, an attacker would have to convince them to visit the Web site, typically by getting them to click a link that takes them to the attacker's site, and then convince them to open the specially crafted Excel file.
What systems are primarily at risk from the vulnerability?
Systems where Microsoft Office Excel is used, including workstations and terminal servers, are primarily at risk. Servers could be at more risk if administrators allow users to log on to servers and to run programs. However, best practices strongly discourage allowing this.
What does the update do?
This update addresses the vulnerability by changing the way that Microsoft Office Excel parses malformed chart sheet substreams in specially crafted Excel files.
When this security bulletin was issued, had this vulnerability been publicly disclosed?
No. Microsoft received information about this vulnerability through responsible disclosure.
When this security bulletin was issued, had Microsoft received any reports that this vulnerability was being exploited?
No. Microsoft had not received any information to indicate that this vulnerability had been publicly used to attack customers when this security bulletin was originally issued.
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Excel Record Memory Corruption Vulnerability - CVE-2010-0824
A remote code execution vulnerability exists in the way that Microsoft Office Excel handles specially crafted Excel files. An attacker who successfully exploited this vulnerability could take complete control of an affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights.
To view this vulnerability as a standard entry in the Common Vulnerabilities and Exposures list, see CVE-2010-0824.
Mitigating Factors for Excel Record Memory Corruption Vulnerability - CVE-2010-0824
Mitigation refers to a setting, common configuration, or general best-practice, existing in a default state, that could reduce the severity of exploitation of a vulnerability. The following mitigating factors may be helpful in your situation:
•
An attacker who successfully exploited this vulnerability could gain the same user rights as the local user. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights.
•
In a Web-based attack scenario, an attacker could host a Web site that contains a Web page that is used to exploit this vulnerability. In addition, compromised Web sites and Web sites that accept or host user-provided content or advertisements could contain specially crafted content that could exploit this vulnerability. In all cases, however, an attacker would have no way to force users to visit these Web sites. Instead, an attacker would have to convince users to visit the Web site, typically by getting them to click a link in an e-mail message or Instant Messenger message that takes users to the attacker’s Web site, and then convince them to open the specially crafted Excel file.
•
The vulnerability cannot be exploited automatically through e-mail. For an attack to be successful a user must open an attachment that is sent in an e-mail message.
Top of sectionTop of section
Workarounds for Excel Record Memory Corruption Vulnerability - CVE-2010-0824
Workaround refers to a setting or configuration change that does not correct the underlying vulnerability but would help block known attack vectors before you apply the update. Microsoft has tested the following workarounds and states in the discussion whether a workaround reduces functionality:
•
Do not open Excel files that you receive from untrusted sources or that you receive unexpectedly from trusted sources. This vulnerability could be exploited when a user opens a specially crafted file.
Top of sectionTop of section
FAQ for Excel Record Memory Corruption Vulnerability - CVE-2010-0824
What is the scope of the vulnerability?
This is a remote code execution vulnerability. An attacker who successfully exploited this vulnerability could take complete control of an affected system remotely. An attacker could then install programs or view, change, or delete data; or create new accounts with full user rights.
What causes the vulnerability?
The vulnerability exists because of the way that Microsoft Office Excel parses the Excel file format when opening a specially crafted Excel file.
What might an attacker use the vulnerability to do?
An attacker who successfully exploited this vulnerability could run arbitrary code as the logged-on user. If a user is logged on with administrative user rights, an attacker could take complete control of the affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights.
How could an attacker exploit the vulnerability?
Exploitation of this vulnerability requires that a user open a specially crafted Excel file with an affected version of Microsoft Office Excel.
In an e-mail attack scenario, an attacker could exploit the vulnerability by sending a specially crafted Excel file to the user and by convincing the user to open the file.
In a Web-based attack scenario, an attacker would have to host a Web site that contains an Excel file that is used to attempt to exploit this vulnerability. In addition, compromised Web sites and Web sites that accept or host user-provided content could contain specially crafted content that could exploit this vulnerability. An attacker would have no way to force users to visit a specially crafted Web site. Instead, an attacker would have to convince them to visit the Web site, typically by getting them to click a link that takes them to the attacker's site, and then convince them to open the specially crafted Excel file.
What systems are primarily at risk from the vulnerability?
Systems where Microsoft Office Excel is used, including workstations and terminal servers, are primarily at risk. Servers could be at more risk if administrators allow users to log on to servers and to run programs. However, best practices strongly discourage allowing this.
What does the update do?
This update addresses the vulnerability by changing the way that Microsoft Office Excel parses specially crafted Excel files.
When this security bulletin was issued, had this vulnerability been publicly disclosed?
No. Microsoft received information about this vulnerability through responsible disclosure.
When this security bulletin was issued, had Microsoft received any reports that this vulnerability was being exploited?
No. Microsoft had not received any information to indicate that this vulnerability had been publicly used to attack customers when this security bulletin was originally issued.
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Excel Record Memory Corruption Vulnerability - CVE-2010-1245
A remote code execution vulnerability exists in the way that Microsoft Office Excel handles specially crafted Excel files. An attacker who successfully exploited this vulnerability could take complete control of an affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights.
To view this vulnerability as a standard entry in the Common Vulnerabilities and Exposures list, see CVE-2010-1245.
Mitigating Factors for Excel Record Memory Corruption Vulnerability - CVE-2010-1245
Mitigation refers to a setting, common configuration, or general best-practice, existing in a default state, that could reduce the severity of exploitation of a vulnerability. The following mitigating factors may be helpful in your situation:
•
An attacker who successfully exploited this vulnerability could gain the same user rights as the local user. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights.
•
In a Web-based attack scenario, an attacker could host a Web site that contains a Web page that is used to exploit this vulnerability. In addition, compromised Web sites and Web sites that accept or host user-provided content or advertisements could contain specially crafted content that could exploit this vulnerability. In all cases, however, an attacker would have no way to force users to visit these Web sites. Instead, an attacker would have to convince users to visit the Web site, typically by getting them to click a link in an e-mail message or Instant Messenger message that takes users to the attacker’s Web site, and then convince them to open the specially crafted Excel file.
•
The vulnerability cannot be exploited automatically through e-mail. For an attack to be successful a user must open an attachment that is sent in an e-mail message.
Top of sectionTop of section
Workarounds for Excel Record Memory Corruption Vulnerability - CVE-2010-1245
Workaround refers to a setting or configuration change that does not correct the underlying vulnerability but would help block known attack vectors before you apply the update. Microsoft has tested the following workarounds and states in the discussion whether a workaround reduces functionality:
•
Do not open Excel files that you receive from untrusted sources or that you receive unexpectedly from trusted sources. This vulnerability could be exploited when a user opens a specially crafted file.
Top of sectionTop of section
FAQ for Excel Record Memory Corruption Vulnerability - CVE-2010-1245
What is the scope of the vulnerability?
This is a remote code execution vulnerability. An attacker who successfully exploited this vulnerability could take complete control of an affected system remotely. An attacker could then install programs or view, change, or delete data; or create new accounts with full user rights.
What causes the vulnerability?
The vulnerability exists because of the way that Microsoft Office Excel parses the Excel file format when opening a specially crafted Excel file.
What might an attacker use the vulnerability to do?
An attacker who successfully exploited this vulnerability could run arbitrary code as the logged-on user. If a user is logged on with administrative user rights, an attacker could take complete control of the affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights.
How could an attacker exploit the vulnerability?
Exploitation of this vulnerability requires that a user open a specially crafted Excel file with an affected version of Microsoft Office Excel.
In an e-mail attack scenario, an attacker could exploit the vulnerability by sending a specially crafted Excel file to the user and by convincing the user to open the file.
In a Web-based attack scenario, an attacker would have to host a Web site that contains an Excel file that is used to attempt to exploit this vulnerability. In addition, compromised Web sites and Web sites that accept or host user-provided content could contain specially crafted content that could exploit this vulnerability. An attacker would have no way to force users to visit a specially crafted Web site. Instead, an attacker would have to convince them to visit the Web site, typically by getting them to click a link that takes them to the attacker's site, and then convince them to open the specially crafted Excel file.
What systems are primarily at risk from the vulnerability?
Systems where Microsoft Office Excel is used, including workstations and terminal servers, are primarily at risk. Servers could be at more risk if administrators allow users to log on to servers and to run programs. However, best practices strongly discourage allowing this.
What does the update do?
This update addresses the vulnerability by changing the way that Microsoft Office Excel parses specially crafted Excel files.
When this security bulletin was issued, had this vulnerability been publicly disclosed?
No. Microsoft received information about this vulnerability through responsible disclosure.
When this security bulletin was issued, had Microsoft received any reports that this vulnerability was being exploited?
No. Microsoft had not received any information to indicate that this vulnerability had been publicly used to attack customers when this security bulletin was originally issued.
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Excel RTD Memory Corruption Vulnerability - CVE-2010-1246
A remote code execution vulnerability exists in the way that Microsoft Office Excel handles specially crafted Excel files. An attacker who successfully exploited this vulnerability could take complete control of an affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights.
To view this vulnerability as a standard entry in the Common Vulnerabilities and Exposures list, see CVE-2010-1246.
Mitigating Factors for Excel RTD Memory Corruption Vulnerability - CVE-2010-1246
Mitigation refers to a setting, common configuration, or general best-practice, existing in a default state, that could reduce the severity of exploitation of a vulnerability. The following mitigating factors may be helpful in your situation:
•
An attacker who successfully exploited this vulnerability could gain the same user rights as the local user. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights.
•
In a Web-based attack scenario, an attacker could host a Web site that contains a Web page that is used to exploit this vulnerability. In addition, compromised Web sites and Web sites that accept or host user-provided content or advertisements could contain specially crafted content that could exploit this vulnerability. In all cases, however, an attacker would have no way to force users to visit these Web sites. Instead, an attacker would have to convince users to visit the Web site, typically by getting them to click a link in an e-mail message or Instant Messenger message that takes users to the attacker’s Web site, and then convince them to open the specially crafted Excel file.
•
The vulnerability cannot be exploited automatically through e-mail. For an attack to be successful a user must open an attachment that is sent in an e-mail message.
Top of sectionTop of section
Workarounds for Excel RTD Memory Corruption Vulnerability - CVE-2010-1246
Workaround refers to a setting or configuration change that does not correct the underlying vulnerability but would help block known attack vectors before you apply the update. Microsoft has tested the following workarounds and states in the discussion whether a workaround reduces functionality:
•
Do not open Excel files that you receive from untrusted sources or that you receive unexpectedly from trusted sources. This vulnerability could be exploited when a user opens a specially crafted file.
Top of sectionTop of section
FAQ for Excel RTD Memory Corruption Vulnerability - CVE-2010-1246
What is the scope of the vulnerability?
This is a remote code execution vulnerability. An attacker who successfully exploited this vulnerability could take complete control of an affected system remotely. An attacker could then install programs or view, change, or delete data; or create new accounts with full user rights.
What causes the vulnerability?
The vulnerability exists because of the way that Microsoft Office Excel parses the Excel file format when opening a specially crafted Excel file.
What might an attacker use the vulnerability to do?
An attacker who successfully exploited this vulnerability could run arbitrary code as the logged-on user. If a user is logged on with administrative user rights, an attacker could take complete control of the affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights.
How could an attacker exploit the vulnerability?
Exploitation of this vulnerability requires that a user open a specially crafted Excel file with an affected version of Microsoft Office Excel.
In an e-mail attack scenario, an attacker could exploit the vulnerability by sending a specially crafted Excel file to the user and by convincing the user to open the file.
In a Web-based attack scenario, an attacker would have to host a Web site that contains an Excel file that is used to attempt to exploit this vulnerability. In addition, compromised Web sites and Web sites that accept or host user-provided content could contain specially crafted content that could exploit this vulnerability. An attacker would have no way to force users to visit a specially crafted Web site. Instead, an attacker would have to convince them to visit the Web site, typically by getting them to click a link that takes them to the attacker's site, and then convince them to open the specially crafted Excel file.
What systems are primarily at risk from the vulnerability?
Systems where Microsoft Office Excel is used, including workstations and terminal servers, are primarily at risk. Servers could be at more risk if administrators allow users to log on to servers and to run programs. However, best practices strongly discourage allowing this.
What does the update do?
This update addresses the vulnerability by changing the way that Microsoft Office Excel parses specially crafted Excel files.
When this security bulletin was issued, had this vulnerability been publicly disclosed?
No. Microsoft received information about this vulnerability through responsible disclosure.
When this security bulletin was issued, had Microsoft received any reports that this vulnerability was being exploited?
No. Microsoft had not received any information to indicate that this vulnerability had been publicly used to attack customers when this security bulletin was originally issued.
Top of sectionTop of section
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Excel Memory Corruption Vulnerability - CVE-2010-1247
A remote code execution vulnerability exists in the way that Microsoft Office Excel handles specially crafted Excel files. An attacker who successfully exploited this vulnerability could take complete control of an affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights.
To view this vulnerability as a standard entry in the Common Vulnerabilities and Exposures list, see CVE-2010-1247.
Mitigating Factors for Excel Memory Corruption Vulnerability - CVE-2010-1247
Mitigation refers to a setting, common configuration, or general best-practice, existing in a default state, that could reduce the severity of exploitation of a vulnerability. The following mitigating factors may be helpful in your situation:
•
An attacker who successfully exploited this vulnerability could gain the same user rights as the local user. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights.
•
In a Web-based attack scenario, an attacker could host a Web site that contains a Web page that is used to exploit this vulnerability. In addition, compromised Web sites and Web sites that accept or host user-provided content or advertisements could contain specially crafted content that could exploit this vulnerability. In all cases, however, an attacker would have no way to force users to visit these Web sites. Instead, an attacker would have to convince users to visit the Web site, typically by getting them to click a link in an e-mail message or Instant Messenger message that takes users to the attacker’s Web site, and then convince them to open the specially crafted Excel file.
•
The vulnerability cannot be exploited automatically through e-mail. For an attack to be successful a user must open an attachment that is sent in an e-mail message.
Top of sectionTop of section
Workarounds for Excel Memory Corruption Vulnerability - CVE-2010-1247
Workaround refers to a setting or configuration change that does not correct the underlying vulnerability but would help block known attack vectors before you apply the update. Microsoft has tested the following workarounds and states in the discussion whether a workaround reduces functionality:
•
Do not open Excel files that you receive from untrusted sources or that you receive unexpectedly from trusted sources. This vulnerability could be exploited when a user opens a specially crafted file.
Top of sectionTop of section
FAQ for Excel Memory Corruption Vulnerability - CVE-2010-1247
What is the scope of the vulnerability?
This is a remote code execution vulnerability. An attacker who successfully exploited this vulnerability could take complete control of an affected system remotely. An attacker could then install programs or view, change, or delete data; or create new accounts with full user rights.
What causes the vulnerability?
The vulnerability exists because of the way that Microsoft Office Excel parses the Excel file format when opening a specially crafted Excel file.
What might an attacker use the vulnerability to do?
An attacker who successfully exploited this vulnerability could run arbitrary code as the logged-on user. If a user is logged on with administrative user rights, an attacker could take complete control of the affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights.
How could an attacker exploit the vulnerability?
Exploitation of this vulnerability requires that a user open a specially crafted Excel file with an affected version of Microsoft Office Excel.
In an e-mail attack scenario, an attacker could exploit the vulnerability by sending a specially crafted Excel file to the user and by convincing the user to open the file.
In a Web-based attack scenario, an attacker would have to host a Web site that contains an Excel file that is used to attempt to exploit this vulnerability. In addition, compromised Web sites and Web sites that accept or host user-provided content could contain specially crafted content that could exploit this vulnerability. An attacker would have no way to force users to visit a specially crafted Web site. Instead, an attacker would have to convince them to visit the Web site, typically by getting them to click a link that takes them to the attacker's site, and then convince them to open the specially crafted Excel file.
What systems are primarily at risk from the vulnerability?
Systems where Microsoft Office Excel is used, including workstations and terminal servers, are primarily at risk. Servers could be at more risk if administrators allow users to log on to servers and to run programs. However, best practices strongly discourage allowing this.
What does the update do?
This update addresses the vulnerability by changing the way that Microsoft Office Excel parses specially crafted Excel files.
When this security bulletin was issued, had this vulnerability been publicly disclosed?
No. Microsoft received information about this vulnerability through responsible disclosure.
When this security bulletin was issued, had Microsoft received any reports that this vulnerability was being exploited?
No. Microsoft had not received any information to indicate that this vulnerability had been publicly used to attack customers when this security bulletin was originally issued.
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Excel HFPicture Memory Corruption Vulnerability - CVE-2010-1248
A remote code execution vulnerability exists in the way that Microsoft Office Excel handles specially crafted Excel files. An attacker who successfully exploited this vulnerability could take complete control of an affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights.
To view this vulnerability as a standard entry in the Common Vulnerabilities and Exposures list, see CVE-2010-1248.
Mitigating Factors for Excel HFPicture Memory Corruption Vulnerability - CVE-2010-1248
Mitigation refers to a setting, common configuration, or general best-practice, existing in a default state, that could reduce the severity of exploitation of a vulnerability. The following mitigating factors may be helpful in your situation:
•
An attacker who successfully exploited this vulnerability could gain the same user rights as the local user. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights.
•
In a Web-based attack scenario, an attacker could host a Web site that contains a Web page that is used to exploit this vulnerability. In addition, compromised Web sites and Web sites that accept or host user-provided content or advertisements could contain specially crafted content that could exploit this vulnerability. In all cases, however, an attacker would have no way to force users to visit these Web sites. Instead, an attacker would have to convince users to visit the Web site, typically by getting them to click a link in an e-mail message or Instant Messenger message that takes users to the attacker’s Web site, and then convince them to open the specially crafted Excel file.
•
The vulnerability cannot be exploited automatically through e-mail. For an attack to be successful a user must open an attachment that is sent in an e-mail message.
Top of sectionTop of section
Workarounds for Excel HFPicture Memory Corruption Vulnerability - CVE-2010-1248
Workaround refers to a setting or configuration change that does not correct the underlying vulnerability but would help block known attack vectors before you apply the update. Microsoft has tested the following workarounds and states in the discussion whether a workaround reduces functionality:
•
Do not open Excel files that you receive from untrusted sources or that you receive unexpectedly from trusted sources. This vulnerability could be exploited when a user opens a specially crafted file.
Top of sectionTop of section
FAQ for Excel HFPicture Memory Corruption Vulnerability - CVE-2010-1248
What is the scope of the vulnerability?
This is a remote code execution vulnerability. An attacker who successfully exploited this vulnerability could take complete control of an affected system remotely. An attacker could then install programs or view, change, or delete data; or create new accounts with full user rights.
What causes the vulnerability?
The vulnerability exists because of the way that Microsoft Office Excel parses the Excel file format when opening a specially crafted Excel file.
What might an attacker use the vulnerability to do?
An attacker who successfully exploited this vulnerability could run arbitrary code as the logged-on user. If a user is logged on with administrative user rights, an attacker could take complete control of the affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights.
How could an attacker exploit the vulnerability?
Exploitation of this vulnerability requires that a user open a specially crafted Excel file with an affected version of Microsoft Office Excel.
In an e-mail attack scenario, an attacker could exploit the vulnerability by sending a specially crafted Excel file to the user and by convincing the user to open the file.
In a Web-based attack scenario, an attacker would have to host a Web site that contains an Excel file that is used to attempt to exploit this vulnerability. In addition, compromised Web sites and Web sites that accept or host user-provided content could contain specially crafted content that could exploit this vulnerability. An attacker would have no way to force users to visit a specially crafted Web site. Instead, an attacker would have to convince them to visit the Web site, typically by getting them to click a link that takes them to the attacker's site, and then convince them to open the specially crafted Excel file.
What systems are primarily at risk from the vulnerability?
Systems where Microsoft Office Excel is used, including workstations and terminal servers, are primarily at risk. Servers could be at more risk if administrators allow users to log on to servers and to run programs. However, best practices strongly discourage allowing this.
What does the update do?
This update addresses the vulnerability by changing the way that Microsoft Office Excel parses specially crafted Excel files.
When this security bulletin was issued, had this vulnerability been publicly disclosed?
No. Microsoft received information about this vulnerability through responsible disclosure.
When this security bulletin was issued, had Microsoft received any reports that this vulnerability was being exploited?
No. Microsoft had not received any information to indicate that this vulnerability had been publicly used to attack customers when this security bulletin was originally issued.
Top of sectionTop of section
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Excel Memory Corruption Vulnerability - CVE-2010-1249
A remote code execution vulnerability exists in the way that Microsoft Office Excel handles specially crafted Excel files. An attacker who successfully exploited this vulnerability could take complete control of an affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights.
To view this vulnerability as a standard entry in the Common Vulnerabilities and Exposures list, see CVE-2010-1249.
Mitigating Factors for Excel Memory Corruption Vulnerability - CVE-2010-1249
Mitigation refers to a setting, common configuration, or general best-practice, existing in a default state, that could reduce the severity of exploitation of a vulnerability. The following mitigating factors may be helpful in your situation:
•
An attacker who successfully exploited this vulnerability could gain the same user rights as the local user. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights.
•
In a Web-based attack scenario, an attacker could host a Web site that contains a Web page that is used to exploit this vulnerability. In addition, compromised Web sites and Web sites that accept or host user-provided content or advertisements could contain specially crafted content that could exploit this vulnerability. In all cases, however, an attacker would have no way to force users to visit these Web sites. Instead, an attacker would have to convince users to visit the Web site, typically by getting them to click a link in an e-mail message or Instant Messenger message that takes users to the attacker’s Web site, and then convince them to open the specially crafted Excel file.
•
The vulnerability cannot be exploited automatically through e-mail. For an attack to be successful a user must open an attachment that is sent in an e-mail message.
Top of sectionTop of section
Workarounds for Excel Memory Corruption Vulnerability - CVE-2010-1249
Workaround refers to a setting or configuration change that does not correct the underlying vulnerability but would help block known attack vectors before you apply the update. Microsoft has tested the following workarounds and states in the discussion whether a workaround reduces functionality:
•
Do not open Excel files that you receive from untrusted sources or that you receive unexpectedly from trusted sources. This vulnerability could be exploited when a user opens a specially crafted file.
Top of sectionTop of section
FAQ for Excel Memory Corruption Vulnerability - CVE-2010-1249
What is the scope of the vulnerability?
This is a remote code execution vulnerability. An attacker who successfully exploited this vulnerability could take complete control of an affected system remotely. An attacker could then install programs or view, change, or delete data; or create new accounts with full user rights.
What causes the vulnerability?
The vulnerability exists because of the way that Microsoft Office Excel parses the Excel file format when opening a specially crafted Excel file.
What might an attacker use the vulnerability to do?
An attacker who successfully exploited this vulnerability could run arbitrary code as the logged-on user. If a user is logged on with administrative user rights, an attacker could take complete control of the affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights.
How could an attacker exploit the vulnerability?
Exploitation of this vulnerability requires that a user open a specially crafted Excel file with an affected version of Microsoft Office Excel.
In an e-mail attack scenario, an attacker could exploit the vulnerability by sending a specially crafted Excel file to the user and by convincing the user to open the file.
In a Web-based attack scenario, an attacker would have to host a Web site that contains an Excel file that is used to attempt to exploit this vulnerability. In addition, compromised Web sites and Web sites that accept or host user-provided content could contain specially crafted content that could exploit this vulnerability. An attacker would have no way to force users to visit a specially crafted Web site. Instead, an attacker would have to convince them to visit the Web site, typically by getting them to click a link that takes them to the attacker's site, and then convince them to open the specially crafted Excel file.
What systems are primarily at risk from the vulnerability?
Systems where Microsoft Office Excel is used, including workstations and terminal servers, are primarily at risk. Servers could be at more risk if administrators allow users to log on to servers and to run programs. However, best practices strongly discourage allowing this.
What does the update do?
This update addresses the vulnerability by changing the way that Microsoft Office Excel parses specially crafted Excel files.
When this security bulletin was issued, had this vulnerability been publicly disclosed?
No. Microsoft received information about this vulnerability through responsible disclosure.
When this security bulletin was issued, had Microsoft received any reports that this vulnerability was being exploited?
No. Microsoft had not received any information to indicate that this vulnerability had been publicly used to attack customers when this security bulletin was originally issued.
Top of sectionTop of section
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Excel EDG Memory Corruption Vulnerability - CVE-2010-1250
A remote code execution vulnerability exists in the way that Microsoft Office Excel handles specially crafted Excel files. An attacker who successfully exploited this vulnerability could take complete control of an affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights.
To view this vulnerability as a standard entry in the Common Vulnerabilities and Exposures list, see CVE-2010-1250.
Mitigating Factors for Excel EDG Memory Corruption Vulnerability - CVE-2010-1250
Mitigation refers to a setting, common configuration, or general best-practice, existing in a default state, that could reduce the severity of exploitation of a vulnerability. The following mitigating factors may be helpful in your situation:
•
An attacker who successfully exploited this vulnerability could gain the same user rights as the local user. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights.
•
In a Web-based attack scenario, an attacker could host a Web site that contains a Web page that is used to exploit this vulnerability. In addition, compromised Web sites and Web sites that accept or host user-provided content or advertisements could contain specially crafted content that could exploit this vulnerability. In all cases, however, an attacker would have no way to force users to visit these Web sites. Instead, an attacker would have to convince users to visit the Web site, typically by getting them to click a link in an e-mail message or Instant Messenger message that takes users to the attacker’s Web site, and then convince them to open the specially crafted Excel file.
•
The vulnerability cannot be exploited automatically through e-mail. For an attack to be successful a user must open an attachment that is sent in an e-mail message.
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Workarounds for Excel EDG Memory Corruption Vulnerability - CVE-2010-1250
Workaround refers to a setting or configuration change that does not correct the underlying vulnerability but would help block known attack vectors before you apply the update. Microsoft has tested the following workarounds and states in the discussion whether a workaround reduces functionality:
•
Do not open Excel files that you receive from untrusted sources or that you receive unexpectedly from trusted sources. This vulnerability could be exploited when a user opens a specially crafted file.
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FAQ for Excel EDG Memory Corruption Vulnerability - CVE-2010-1250
What is the scope of the vulnerability?
This is a remote code execution vulnerability. An attacker who successfully exploited this vulnerability could take complete control of an affected system remotely. An attacker could then install programs or view, change, or delete data; or create new accounts with full user rights.
What causes the vulnerability?
The vulnerability exists because of the way that Microsoft Office Excel parses the Excel file format when opening a specially crafted Excel file.
What might an attacker use the vulnerability to do?
An attacker who successfully exploited this vulnerability could run arbitrary code as the logged-on user. If a user is logged on with administrative user rights, an attacker could take complete control of the affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights.
How could an attacker exploit the vulnerability?
Exploitation of this vulnerability requires that a user open a specially crafted Excel file with an affected version of Microsoft Office Excel.
In an e-mail attack scenario, an attacker could exploit the vulnerability by sending a specially crafted Excel file to the user and by convincing the user to open the file.
In a Web-based attack scenario, an attacker would have to host a Web site that contains an Excel file that is used to attempt to exploit this vulnerability. In addition, compromised Web sites and Web sites that accept or host user-provided content could contain specially crafted content that could exploit this vulnerability. An attacker would have no way to force users to visit a specially crafted Web site. Instead, an attacker would have to convince them to visit the Web site, typically by getting them to click a link that takes them to the attacker's site, and then convince them to open the specially crafted Excel file.
What systems are primarily at risk from the vulnerability?
Systems where Microsoft Office Excel is used, including workstations and terminal servers, are primarily at risk. Servers could be at more risk if administrators allow users to log on to servers and to run programs. However, best practices strongly discourage allowing this.
What does the update do?
This update addresses the vulnerability by changing the way that Microsoft Office Excel parses specially crafted Excel files.
When this security bulletin was issued, had this vulnerability been publicly disclosed?
No. Microsoft received information about this vulnerability through responsible disclosure.
When this security bulletin was issued, had Microsoft received any reports that this vulnerability was being exploited?
No. Microsoft had not received any information to indicate that this vulnerability had been publicly used to attack customers when this security bulletin was originally issued.
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Excel Record Stack Corruption Vulnerability - CVE-2010-1251
A remote code execution vulnerability exists in the way that Microsoft Office Excel handles specially crafted Excel files. An attacker who successfully exploited this vulnerability could take complete control of an affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights.
To view this vulnerability as a standard entry in the Common Vulnerabilities and Exposures list, see CVE-2010-1251.
Mitigating Factors for Excel Record Stack Corruption Vulnerability - CVE-2010-1251
Mitigation refers to a setting, common configuration, or general best-practice, existing in a default state, that could reduce the severity of exploitation of a vulnerability. The following mitigating factors may be helpful in your situation:
•
An attacker who successfully exploited this vulnerability could gain the same user rights as the local user. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights.
•
In a Web-based attack scenario, an attacker could host a Web site that contains a Web page that is used to exploit this vulnerability. In addition, compromised Web sites and Web sites that accept or host user-provided content or advertisements could contain specially crafted content that could exploit this vulnerability. In all cases, however, an attacker would have no way to force users to visit these Web sites. Instead, an attacker would have to convince users to visit the Web site, typically by getting them to click a link in an e-mail message or Instant Messenger message that takes users to the attacker’s Web site, and then convince them to open the specially crafted Excel file.
•
The vulnerability cannot be exploited automatically through e-mail. For an attack to be successful a user must open an attachment that is sent in an e-mail message.
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Workarounds for Excel Record Stack Corruption Vulnerability - CVE-2010-1251
Workaround refers to a setting or configuration change that does not correct the underlying vulnerability but would help block known attack vectors before you apply the update. Microsoft has tested the following workarounds and states in the discussion whether a workaround reduces functionality:
•
Do not open Excel files that you receive from untrusted sources or that you receive unexpectedly from trusted sources. This vulnerability could be exploited when a user opens a specially crafted file.
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FAQ for Excel Record Stack Corruption Vulnerability - CVE-2010-1251
What is the scope of the vulnerability?
This is a remote code execution vulnerability. An attacker who successfully exploited this vulnerability could take complete control of an affected system remotely. An attacker could then install programs or view, change, or delete data; or create new accounts with full user rights.
What causes the vulnerability?
The vulnerability exists because of the way that Microsoft Office Excel parses the Excel file format when opening a specially crafted Excel file.
What might an attacker use the vulnerability to do?
An attacker who successfully exploited this vulnerability could run arbitrary code as the logged-on user. If a user is logged on with administrative user rights, an attacker could take complete control of the affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights.
How could an attacker exploit the vulnerability?
Exploitation of this vulnerability requires that a user open a specially crafted Excel file with an affected version of Microsoft Office Excel.
In an e-mail attack scenario, an attacker could exploit the vulnerability by sending a specially crafted Excel file to the user and by convincing the user to open the file.
In a Web-based attack scenario, an attacker would have to host a Web site that contains an Excel file that is used to attempt to exploit this vulnerability. In addition, compromised Web sites and Web sites that accept or host user-provided content could contain specially crafted content that could exploit this vulnerability. An attacker would have no way to force users to visit a specially crafted Web site. Instead, an attacker would have to convince them to visit the Web site, typically by getting them to click a link that takes them to the attacker's site, and then convince them to open the specially crafted Excel file.
What systems are primarily at risk from the vulnerability?
Systems where Microsoft Office Excel is used, including workstations and terminal servers, are primarily at risk. Servers could be at more risk if administrators allow users to log on to servers and to run programs. However, best practices strongly discourage allowing this.
What does the update do?
This update addresses the vulnerability by changing the way that Microsoft Office Excel parses specially crafted Excel files.
When this security bulletin was issued, had this vulnerability been publicly disclosed?
No. Microsoft received information about this vulnerability through responsible disclosure.
When this security bulletin was issued, had Microsoft received any reports that this vulnerability was being exploited?
No. Microsoft had not received any information to indicate that this vulnerability had been publicly used to attack customers when this security bulletin was originally issued.
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Excel String Variable Vulnerability - CVE-2010-1252
A remote code execution vulnerability exists in the way that Microsoft Office Excel handles specially crafted Excel files. An attacker who successfully exploited this vulnerability could take complete control of an affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights.
To view this vulnerability as a standard entry in the Common Vulnerabilities and Exposures list, see CVE-2010-1252.
Mitigating Factors for Excel String Variable Vulnerability - CVE-2010-1252
Mitigation refers to a setting, common configuration, or general best-practice, existing in a default state, that could reduce the severity of exploitation of a vulnerability. The following mitigating factors may be helpful in your situation:
•
An attacker who successfully exploited this vulnerability could gain the same user rights as the local user. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights.
•
In a Web-based attack scenario, an attacker could host a Web site that contains a Web page that is used to exploit this vulnerability. In addition, compromised Web sites and Web sites that accept or host user-provided content or advertisements could contain specially crafted content that could exploit this vulnerability. In all cases, however, an attacker would have no way to force users to visit these Web sites. Instead, an attacker would have to convince users to visit the Web site, typically by getting them to click a link in an e-mail message or Instant Messenger message that takes users to the attacker’s Web site, and then convince them to open the specially crafted Excel file.
•
The vulnerability cannot be exploited automatically through e-mail. For an attack to be successful a user must open an attachment that is sent in an e-mail message.
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Workarounds for Excel String Variable Vulnerability - CVE-2010-1252
Workaround refers to a setting or configuration change that does not correct the underlying vulnerability but would help block known attack vectors before you apply the update. Microsoft has tested the following workarounds and states in the discussion whether a workaround reduces functionality:
•
Do not open Excel files that you receive from untrusted sources or that you receive unexpectedly from trusted sources. This vulnerability could be exploited when a user opens a specially crafted file.
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FAQ for Excel String Variable Vulnerability - CVE-2010-1252
What is the scope of the vulnerability?
This is a remote code execution vulnerability. An attacker who successfully exploited this vulnerability could take complete control of an affected system remotely. An attacker could then install programs or view, change, or delete data; or create new accounts with full user rights.
What causes the vulnerability?
The vulnerability exists because of the way that Microsoft Office Excel parses the Excel file format when opening a specially crafted Excel file.
What might an attacker use the vulnerability to do?
An attacker who successfully exploited this vulnerability could run arbitrary code as the logged-on user. If a user is logged on with administrative user rights, an attacker could take complete control of the affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights.
How could an attacker exploit the vulnerability?
Exploitation of this vulnerability requires that a user open a specially crafted Excel file with an affected version of Microsoft Office Excel.
In an e-mail attack scenario, an attacker could exploit the vulnerability by sending a specially crafted Excel file to the user and by convincing the user to open the file.
In a Web-based attack scenario, an attacker would have to host a Web site that contains an Excel file that is used to attempt to exploit this vulnerability. In addition, compromised Web sites and Web sites that accept or host user-provided content could contain specially crafted content that could exploit this vulnerability. An attacker would have no way to force users to visit a specially crafted Web site. Instead, an attacker would have to convince them to visit the Web site, typically by getting them to click a link that takes them to the attacker's site, and then convince them to open the specially crafted Excel file.
What systems are primarily at risk from the vulnerability?
Systems where Microsoft Office Excel is used, including workstations and terminal servers, are primarily at risk. Servers could be at more risk if administrators allow users to log on to servers and to run programs. However, best practices strongly discourage allowing this.
What does the update do?
This update addresses the vulnerability by changing the way that Microsoft Office Excel parses specially crafted Excel files.
When this security bulletin was issued, had this vulnerability been publicly disclosed?
No. Microsoft received information about this vulnerability through responsible disclosure.
When this security bulletin was issued, had Microsoft received any reports that this vulnerability was being exploited?
No. Microsoft had not received any information to indicate that this vulnerability had been publicly used to attack customers when this security bulletin was originally issued.
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Excel ADO Object Vulnerability - CVE-2010-1253
A remote code execution vulnerability exists in the way that Microsoft Office Excel handles specially crafted Excel files. An attacker who successfully exploited this vulnerability could take complete control of an affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights.
To view this vulnerability as a standard entry in the Common Vulnerabilities and Exposures list, see CVE-2010-1253.
Mitigating Factors for Excel ADO Object Vulnerability - CVE-2010-1253
Mitigation refers to a setting, common configuration, or general best-practice, existing in a default state, that could reduce the severity of exploitation of a vulnerability. The following mitigating factors may be helpful in your situation:
•
An attacker who successfully exploited this vulnerability could gain the same user rights as the local user. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights.
•
In a Web-based attack scenario, an attacker could host a Web site that contains a Web page that is used to exploit this vulnerability. In addition, compromised Web sites and Web sites that accept or host user-provided content or advertisements could contain specially crafted content that could exploit this vulnerability. In all cases, however, an attacker would have no way to force users to visit these Web sites. Instead, an attacker would have to convince users to visit the Web site, typically by getting them to click a link in an e-mail message or Instant Messenger message that takes users to the attacker’s Web site, and then convince them to open the specially crafted Excel file.
•
The vulnerability cannot be exploited automatically through e-mail. For an attack to be successful a user must open an attachment that is sent in an e-mail message.
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Workarounds for Excel ADO Object Vulnerability - CVE-2010-1253
Workaround refers to a setting or configuration change that does not correct the underlying vulnerability but would help block known attack vectors before you apply the update. Microsoft has tested the following workarounds and states in the discussion whether a workaround reduces functionality:
•
Use Microsoft Office File Block policy to block the opening of Office 2003 and earlier documents from unknown or untrusted sources and locations
The following registry scripts can be used to set the File Block policy.
Note Modifying the Registry incorrectly can cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that problems resulting from incorrect modification of the Registry can be solved. Modify the Registry at your own risk.
•
For Office 2003
Windows Registry Editor Version 5.00
[HKEY_CURRENT_USER\Software\Microsoft\Office\11.0\Excel\Security\FileOpenBlock]
"BinaryFiles"=dword:00000001
Note In order to use 'FileOpenBlock' with Microsoft Office 2003, all of the latest security updates for Microsoft Office 2003 must be applied.
•
For 2007 Office system
Windows Registry Editor Version 5.00
[HKEY_CURRENT_USER\Software\Policies\Microsoft\Office\12.0\Excel\Security\FileOpenBlock]
"BinaryFiles"=dword:00000001
Note In order to use 'FileOpenBlock' with the 2007 Microsoft Office system, all of the latest security updates for the 2007 Microsoft Office system must be applied.
Impact of workaround. Users who have configured the File Block policy and have not configured a special "exempt directory" as discussed in Microsoft Knowledge Base Article 922848 will be unable to open Office 2003 files or earlier versions in Office 2003 or 2007 Microsoft Office System.
How to undo the workaround:
•
For Office 2003
Windows Registry Editor Version 5.00
[HKEY_CURRENT_USER\Software\Microsoft\Office\11.0\Excel\Security\FileOpenBlock]
"BinaryFiles"=dword:00000000
•
For 2007 Office system
Windows Registry Editor Version 5.00
[HKEY_CURRENT_USER\Software\Policies\Microsoft\Office\12.0\Excel\Security\FileOpenBlock]
"BinaryFiles"=dword:00000000
•
Use the Microsoft Office Isolated Conversion Environment (MOICE) when opening files from unknown or untrusted sources
The Microsoft Office Isolated Conversion Environment (MOICE) helps protect Office 2003 installations by more securely opening Word, Excel, and PowerPoint binary format files.
To install MOICE, you must have Office 2003 or 2007 Office system installed.
To install MOICE, you must have the Compatibility Pack for Word, Excel, and PowerPoint 2007 File Formats. The compatibility pack is available as a free download from the Microsoft Download Center:
Download the FileFormatConverters.exe package now
MOICE requires all updates that are recommended for all Office programs. Visit Microsoft Update to install all recommended updates:
http://update.microsoft.com/microsoftupdate/v6/default.aspx?ln=en-us
For Excel
To enable MOICE, change the registered handler for the .xls, .xlt, and .xla file formats. The following table describes the command to enable or to disable MOICE for the .xls, .xlt, and .xla file formats:
Command to enable MOICE to be the registered handler Command to disable MOICE as the registered handler
ASSOC .XLS=oice.excel.sheet
ASSOC .xls=Excel.Sheet.8
ASSOC .XLT=oice.excel.template
ASSOC .xlt=Excel.Template
ASSOC .XLA=oice.excel.addin
ASSOC .xla=Excel.Addin
Note On Windows Vista, Windows Server 2008, Windows 7, and Windows Server 2008 R2, the commands above will need to be run from an elevated command prompt.
For more information on MOICE, see Microsoft Knowledge Base Article 935865.
Impact of workaround. Office 2003 and earlier formatted documents that are converted to the 2007 Microsoft Office System Open XML format by MOICE will not retain macro functionality. Additionally, documents with passwords or that are protected with Digital Rights Management cannot be converted.
•
Do not open Excel files that you receive from untrusted sources or that you receive unexpectedly from trusted sources. This vulnerability could be exploited when a user opens a specially crafted file.
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FAQ for Excel ADO Object Vulnerability - CVE-2010-1253
What is the scope of the vulnerability?
This is a remote code execution vulnerability. An attacker who successfully exploited this vulnerability could take complete control of an affected system remotely. An attacker could then install programs or view, change, or delete data; or create new accounts with full user rights.
What causes the vulnerability?
The vulnerability exists because of the way that Microsoft Office Excel parses the Excel file format when opening a specially crafted Excel file.
What might an attacker use the vulnerability to do?
An attacker who successfully exploited this vulnerability could run arbitrary code as the logged-on user. If a user is logged on with administrative user rights, an attacker could take complete control of the affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights.
How could an attacker exploit the vulnerability?
Exploitation of this vulnerability requires that a user open a specially crafted Excel file with an affected version of Microsoft Office Excel.
In an e-mail attack scenario, an attacker could exploit the vulnerability by sending a specially crafted Excel file to the user and by convincing the user to open the file.
In a Web-based attack scenario, an attacker would have to host a Web site that contains an Excel file that is used to attempt to exploit this vulnerability. In addition, compromised Web sites and Web sites that accept or host user-provided content could contain specially crafted content that could exploit this vulnerability. An attacker would have no way to force users to visit a specially crafted Web site. Instead, an attacker would have to convince them to visit the Web site, typically by getting them to click a link that takes them to the attacker's site, and then convince them to open the specially crafted Excel file.
What systems are primarily at risk from the vulnerability?
Systems where Microsoft Office Excel is used, including workstations and terminal servers, are primarily at risk. Servers could be at more risk if administrators allow users to log on to servers and to run programs. However, best practices strongly discourage allowing this.
What does the update do?
This update addresses the vulnerability by changing the way that Microsoft Office Excel parses specially crafted Excel files.
When this security bulletin was issued, had this vulnerability been publicly disclosed?
No. Microsoft received information about this vulnerability through responsible disclosure.
When this security bulletin was issued, had Microsoft received any reports that this vulnerability was being exploited?
No. Microsoft had not received any information to indicate that this vulnerability had been publicly used to attack customers when this security bulletin was originally issued.
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Mac Office Open XML Permissions Vulnerability - CVE-2010-1254
An elevation of privilege vulnerability exists in the way that the Open XML File Format Converter for Mac installs itself. During installation, the Open XML File Format Converter for Mac changes the file system ACLs on the /Applications folder in a way that reduces the security settings on the /Applications folder and allows all access to the files in this folder. To exploit this vulnerability, an attacker would first have to log on to the system. An attacker could replace the Open XML File Format Converter for Mac with a malicious executable. When an administrator later logs on and runs the Open XML File Format Converter for Mac, the attacker-provided code can be made to execute, allowing the attacker to take complete control over an affected system.
To view this vulnerability as a standard entry in the Common Vulnerabilities and Exposures list, see CVE-2010-1254.
Mitigating Factors for Mac Office Open XML Permissions Vulnerability - CVE-2010-1254
Mitigation refers to a setting, common configuration, or general best-practice, existing in a default state, that could reduce the severity of exploitation of a vulnerability. The following mitigating factors may be helpful in your situation:
•
An attacker must have valid logon credentials and be able to log on locally to exploit this vulnerability.
•
The Open XML File Format Converter for Mac is not installed with any version of Office for Mac. It is only available as a separate download.
•
The attacker would only be able to gain elevated privileges on the affected Mac computer if an Administrator executed the Open XML File Format Converter for Mac after the attacker had modified the installation. This is not a direct elevation of privilege, but rather it is a luring attack.
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Workarounds for Mac Office Open XML Permissions Vulnerability - CVE-2010-1254
Workaround refers to a setting or configuration change that does not correct the underlying vulnerability but would help block known attack vectors before you apply the update. Microsoft has tested the following workarounds and states in the discussion whether a workaround reduces functionality:
•
Change owner and group of /Applications folder and Open XML File Format Converter for Macto privileged user
Run the following commands in the Terminal application to set permissions:
sudo chown root:admin /Applications
sudo chown -R root:admin /Applications/Open\ XML\ Converter.app
How to undo the workaround.
To reset permissions back to the vulnerable state set by Open XML File Format Converter for Mac installation:
sudo chown 99:99/Applications
sudo chown -R 99:99/Applications/Open\ XML\ Converter.app
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FAQ for Mac Office Open XML Permissions Vulnerability - CVE-2010-1254
What is the scope of the vulnerability?
This is an elevation of privilege vulnerability. An attacker who successfully exploited this vulnerability could take complete control of an affected system remotely. An attacker could then install programs or view, change, or delete data; or create new accounts with full user rights.
What causes the vulnerability?
During installation, the Office XML converter for Mac application changes the file system ACLs on the /Applications folder in a way that reduces the security settings on the /Applications folder.
What might an attacker use the vulnerability to do?
An attacker could replace the Office XML Converter for Mac application with a malicious executable. When an administrator later logs on and runs the Office XML Converter for Mac application, attacker-provided code can be made to execute, allowing the attacker to take complete control over an affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights.
How could an attacker exploit the vulnerability?
To exploit this vulnerability, an attacker would first have to log on to the system and replace the Open XML File Format Converter for Mac with a malicious executable. When an administrator later logs on and runs the Office XML Converter for Mac application, the attacker-provided code can be made to execute.
What systems are primarily at risk from the vulnerability?
Workstations and terminal servers are primarily at risk. Servers could be at more risk if administrators allow users to log on to servers and to run programs. However, best practices strongly discourage allowing this.
What does the update do?
The update addresses the vulnerability by correcting the way that the Open XML File Format Converter for Mac installs so that the default security settings of the /Applications folder are not changed.
When this security bulletin was issued, had this vulnerability been publicly disclosed?
No. Microsoft received information about this vulnerability through responsible disclosure.
When this security bulletin was issued, had Microsoft received any reports that this vulnerability was being exploited?
No. Microsoft had not received any information to indicate that this vulnerability had been publicly used to attack customers when this security bulletin was originally issued.
Other Information
Acknowledgments
Microsoft thanks the following for working with us to help protect customers:
•
An anonymous researcher, working with TippingPoint's Zero Day Initiative, for reporting the Excel Record Parsing Memory Corruption Vulnerability (CVE-2010-0821)
•
Nicolas Joly of VUPEN Vulnerability Research Team for reporting the Excel Object Stack Overflow Vulnerability (CVE-2010-0822)
•
Bing Liu of Fortinet's FortiGuard Labs for reporting Excel Memory Corruption Vulnerability (CVE-2010-0823)
•
Nicolas Joly of VUPEN Vulnerability Research Team for reporting the Excel Record Memory Corruption Vulnerability (CVE-2010-0824)
•
Nicolas Joly of VUPEN Vulnerability Research Team for reporting the Excel Record Memory Corruption Vulnerability (CVE-2010-1245)
•
Nicolas Joly of VUPEN Vulnerability Research Team for reporting the Excel RTD Memory Corruption Vulnerability (CVE-2010-1246)
•
Nicolas Joly of the VUPEN Vulnerability Research Team for reporting the Excel Memory Corruption Vulnerability (CVE-2010-1247)
•
Nicolas Joly of VUPEN Vulnerability Research Team for reporting the Excel HFPicture Memory Corruption Vulnerability (CVE-2010-1248)
•
Nicolas Joly of VUPEN Vulnerability Research Team for reporting the Excel Memory Corruption Vulnerability (CVE-2010-1249)
•
Nicolas Joly of VUPEN Vulnerability Research Team for reporting the Excel EDG Memory Corruption Vulnerability (CVE-2010-1250)
•
Carsten Eiram of Secunia for reporting the Excel Record Stack Corruption Vulnerability (CVE-2010-1251)
•
Carsten Eiram of Secunia for reporting the Excel String Variable Vulnerability (CVE-2010-1252)
•
An anonymous researcher, working with TippingPoint's Zero Day Initiative, for reporting the Excel ADO Object Vulnerability (CVE-2010-1253)
•
Rick Glaspie of Gilbert Public Schools in Gilbert, AZ for reporting the Mac Office Open XML Permissions Vulnerability (CVE-2010-1254)
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Microsoft Active Protections Program (MAPP)
To improve security protections for customers, Microsoft provides vulnerability information to major security software providers in advance of each monthly security update release. Security software providers can then use this vulnerability information to provide updated protections to customers via their security software or devices, such as antivirus, network-based intrusion detection systems, or host-based intrusion prevention systems. To determine whether active protections are available from security software providers, please visit the active protections Web sites provided by program partners, listed in Microsoft Active Protections Program (MAPP) Partners.
Support
•
Customers in the U.S. and Canada can receive technical support from Security Support or 1-866-PCSAFETY. There is no charge for support calls that are associated with security updates. For more information about available support options, see Microsoft Help and Support.
•
International customers can receive support from their local Microsoft subsidiaries. There is no charge for support that is associated with security updates. For more information about how to contact Microsoft for support issues, visit the International Support Web site.
Disclaimer
The information provided in the Microsoft Knowledge Base is provided "as is" without warranty of any kind. Microsoft disclaims all warranties, either express or implied, including the warranties of merchantability and fitness for a particular purpose. In no event shall Microsoft Corporation or its suppliers be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages, even if Microsoft Corporation or its suppliers have been advised of the possibility of such damages. Some states do not allow the exclusion or limitation of liability for consequential or incidental damages so the foregoing limitation may not apply.
Revisions
•
V1.0 (June 8, 2010): Bulletin published.
Related
