Microsoft released a security advisory [1] with details about a so far unpatched vulnerability in the canonical display driver. All system with the "Aero" theme enabled are vulnerable.

Theoretically, code execution is possible, but according to Microsoft unlikely. However, the vulnerability would allow a DoS attack by crashing the system. The quick fix for the problem is to turn off aero.

[1] http://www.microsoft.com/technet/security/advisory/2028859.mspx

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Johannes B. Ullrich, Ph.D.
SANS Technology Institute
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