Risk
High

Date Discovered
7/14/2009 12:00:00 AM

Description
Microsoft DirectX is prone to a remote code-execution vulnerability that resides in the DirectShow component.Successful exploits allow remote attackers to execute arbitrary code in the context of the user running the application that uses DirectX. Failed exploit attempts will result in a denial-of-service condition.

Technologies Affected
Microsoft DirectX 9.0 b
Microsoft DirectX 9.0 c
Microsoft DirectX 9.0 a
Microsoft DirectX 9.0
Microsoft DirectX 8.1
Microsoft DirectX 7.0

Recommendations
Run all software as a nonprivileged user with minimal access rights.
To limit the potential damage that a successful exploit may achieve, run all nonadministrative software as a regular user with the least amount of privileges required to successfully operate.
Do not accept or execute files from untrusted or unknown sources.
To reduce the likelihood of successful exploits, never handle files that originate from unfamiliar or untrusted sources.
Do not follow links provided by unknown or untrusted sources.
Web users should be cautious about following links to sites that are provided by unfamiliar or suspicious sources. Filtering HTML from emails may help remove a possible vector for transmitting malicious links to users.
Implement multiple redundant layers of security.
Since this issue may be leveraged to execute code, we recommend memory-protection schemes, such as nonexecutable stack/heap configurations and randomly mapped memory segments. This tactic may complicate exploits of memory-corruption vulnerabilities.

The vendor has released an update. Please see the references for details.

References
Source: Microsoft Security Bulletin MS09-028
URL: http://www.microsoft.com/technet/security/Bulletin/MS09-028.mspx

Source: Microsoft DirectX Homepage
URL: http://msdn.microsoft.com/directx/

Credits
TippingPoint and the Zero Day Initiative, Thomas Garnier of SkyRecon, and Yamata Li of Palo Alto Networks