CVE-2013-3660: Microsoft Win32k Privilege Escalation Vulnerability

High severity, CVSS 7.8. Actively exploited: in CISA KEV since 2022-03-28. EPSS: 39.3% chance of exploitation in the next 30 days.

The EPATHOBJ::pprFlattenRec function in win32k.sys in the kernel-mode drivers in Microsoft Windows XP SP2 and SP3, Windows Server 2003 SP2, Windows Vista SP2, Windows Server 2008 SP2 and R2 SP1, Windows 7 SP1, Windows 8, and Windows Server 2012 does not properly initialize a pointer for the next object in a certain list, which allows local users to obtain write access to the PATHRECORD chain, and consequently gain privileges, by triggering excessive consumption of paged memory and then making many FlattenPath function calls, aka "Win32k Read AV Vulnerability."

Affected products

• Microsoft Windows 7: affected versions not specified
• Microsoft Windows 8: affected versions not specified
• Microsoft Windows Rt: affected versions not specified
• Microsoft Windows Server 2003: affected versions not specified
• Microsoft Windows Server 2008: affected versions not specified; version r2 only
• Microsoft Windows Server 2012: affected versions not specified
• Microsoft Windows Vista: affected versions not specified
• Microsoft Windows XP: affected versions not specified

Published 2013-05-24. Last modified 2026-06-16.