known ransomware use

Microsoft Win32k Privilege Escalation Vulnerability

Added to KEV
2022-01-21
Federal due date
2022-07-21
Vendor
Microsoft
Product
Win32k
EPSS
99.2th percentile (score 0.813, as of 2026-06-08)
NVD CVSS v3.1
Ransomware use
Known
Upstream
https://nvd.nist.gov/vuln/detail/CVE-2018-8453

CISA short description

Microsoft Windows Win32k contains a vulnerability that allows an attacker to escalate 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.