Microsoft Win32k Privilege Escalation Vulnerability

Added to KEV
2022-03-28
Federal due date
2022-04-18
Vendor
Microsoft
Product
Win32k
EPSS
98.7th percentile (score 0.706, as of 2026-06-08)
NVD CVSS v3.1
Ransomware use
Unknown
Upstream
https://nvd.nist.gov/vuln/detail/CVE-2013-3660

CISA short description

The EPATHOBJ::pprFlattenRec function in win32k.sys in the kernel-mode drivers in Microsoft does not properly initialize a pointer for the next object in a certain list, which allows local users to gain privileges.

Required action

Apply updates per vendor instructions.

EPSS percentile is the FIRST.org exploit-probability ranking as of the date noted above; it moves daily. CVSS reflects NVD's analysis at time of publication.