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Microsoft Windows CSRSS error handling vulnerability

Vulnerability Note VU#740636

Original Release Date: 2007-04-10 | Last Revised: 2007-04-11


The Microsoft Windows Client/Server Run-time Subsystem (CSRSS) process fails to properly handle error messages. This vulnerability may allow a remote attacker to execute arbitrary code.


According to Microsoft Security Bulletin MS07-021:

CSRSS is the user-mode portion of the Win32 subsystem. CSRSS stands for client/server run-time subsystem and is an essential subsystem that must be running at all times. CSRSS is responsible for console windows, creating and/or deleting threads.
The CSRSS process fails to properly handle error messages possibly allowing a double free vulnerability to occur.

More information is available in Microsoft Security Bulletin MS07-021.

Note that proof-of-concept code is available for this vulnerability.


A remote attacker may be able to execute arbitrary code on a vulnerable system.


Apply update from Microsoft
Microsoft has released an update for this vulnerability in Microsoft Security Bulletin MS07-021.

Vendor Information


Microsoft Corporation Affected

Updated:  April 10, 2007



Vendor Statement

We have not received a statement from the vendor.

Vendor Information

The vendor has not provided us with any further information regarding this vulnerability.


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This vulnerability was reported by Tim Garnett of Determina Security Research .

This document was written by Jeff Gennari.

Other Information

CVE IDs: CVE-2006-6797
Severity Metric: 7.44
Date Public: 2006-12-15
Date First Published: 2007-04-10
Date Last Updated: 2007-04-11 10:50 UTC
Document Revision: 14

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