Malware authors are actively exploiting a zero-day privilege escalation vulnerability in a copy protection application installed by default in Windows XP and Windows 2003, according to a warning from anti-virus vendor Symantec.
The unpatched vulnerability, confirmed in the Macrovision SafeDisc (secdrv.sys) DRM scheme for online games, can be exploited overwrite arbitrary kernel memory and execute arbitrary code with SYSTEM privileges.
This facilitates the complete compromise of affected computers.
An advisory from the NVD (National Vulnerability Database) provides the skinny:
Buffer overflow in Macrovision SafeDisc secdrv.sys, as shipped in Microsoft Windows XP and Server 2003, allows local users to overwrite arbitrary memory locations and gain privileges via a crafted argument to a METHOD_NEITHER IOCTL.
Symantec researcher Elia Florio stumbled upon the flaw while reverse engineering an in-the-wild malware sample and successfully tested the exploit against fully patched Windows XP-SP2 and Windows 2003-SP1 machines. Windows Vista does not seem to be affected by the problem, Florio said.
Immediately after Florio went public with his discovery, researchers at Reverse Mode traced the issue to the Macrovision SafeDisc application. Exploit code (.zip file) for this issue is already in circulation.
A functional exploit is commercially available through the CORE IMPACT penetration testing platform.