Today Microsoft released a security advisory about a vulnerability in the
Animated Cursor processing code in Windows:
http://www.microsoft.com/technet/security/advisory/935423.mspx 

It seems like the vulnerability is already exploited in the wild:
http://asert.arbornetworks.com/2007/03/any-ani-file-could-infect-you/ 

This is one of the vulnerabilities Determina discovered and reported to
Microsoft back in December of last year. It was assigned CVE-2007-0038 and we
published a brief advisory about it today:
http://www.determina.com/security_center/security_advisories/securityadvisory_0day_032907.asp 

The vulnerability is trivially exploitable on all versions of Windows, including
Vista. The protected mode of IE7 will lessen the impact of the vulnerability,
but shellcode execution is of course still possible. Determina also discovered
that under certain circumstances Mozilla Firefox uses the same underlying
Windows code for processing ANI files, and can be exploited similarly to
Internet Explorer.

As noted in Microsoft's security advisory, workarounds for this vulnerability
are limited at this point. I personally recommend browsing the web and reading
mail with telnet until patches are available.

Of course, Determina VPS Desktop and Server Edition have been continuously
protecting against this vulnerability even prior to its discovery.


Alexander Sotirov
Determina Security Research