ZDI-12-156 : Cisco AnyConnect VPN Client Arbitrary Program Instantiation Remote Code Execution Vulnerability

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ZDI-12-156 : Cisco AnyConnect VPN Client Arbitrary Program Instantiation
Remote Code Execution Vulnerability
http://www.zerodayinitiative.com/advisories/ZDI-12-156
August 22, 2012

• – CVE ID:
  CVE-2012-2493

• – CVSS:
  9, AV:N/AC:L/Au:N/C:P/I:P/A:C

• – Affected Vendors:
  Cisco

• – Affected Products:
  Cisco AnyConnect VPN Client

• – Vulnerability Details:
  This vulnerability allows remote attackers to execute arbitrary code on
  vulnerable installations of Cisco AnyConnect VPN Client. User interaction
  is required to exploit this vulnerability in that the target must visit a
  malicious page or open a malicious file.

The specific flaw exists due to insufficient signature checks with the
Cisco AnyConnect VPN Client. When the client is invoked through the ActiveX
control it downloads and checks a file called vpndownloader.exe. This file
has to be properly signed by Cisco. Once this file is downloaded it is run
and downloads additional configuration files. Within the downloaded config
file it is possible to force a download of executable files. Those files
are not properly checked for valid certificates and are run on the host as
soon as they are downloaded.

• – Vendor Response:
  Cisco has issued an update to correct this vulnerability. More details can
  be found at:
  http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco

• -sa-20120620-ac

• – Disclosure Timeline:
  2011-11-22 - Vulnerability reported to vendor
  2012-08-22 - Coordinated public release of advisory

• – Credit:
  This vulnerability was discovered by:

• gwslabs.com

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http://www.zerodayinitiative.com

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