known ransomware use

Microsoft Win32k Privilege Escalation Vulnerability

Added to KEV
2022-03-03
Federal due date
2022-03-24
Vendor
Microsoft
Product
Win32k
EPSS
99.6th percentile (score 0.904, as of 2026-06-08)
NVD CVSS v3.1
Ransomware use
Known
Upstream
https://nvd.nist.gov/vuln/detail/CVE-2015-1701

CISA short description

An unspecified vulnerability exists in the Win32k.sys kernel-mode driver in Microsoft Windows Server that allows a local attacker to execute arbitrary code with elevated 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.