CVE-2018-8639 Known ransomware use

Microsoft Windows Win32k Improper Resource Shutdown or Release Vulnerability

Microsoft — Windows

Added to KEV catalog: 3 March 2025
Federal remediation due date: 24 March 2025
Weakness classification (CWE): CWE-404

CISA Description

Microsoft Windows Win32k contains an improper resource shutdown or release vulnerability that allows for local, authenticated privilege escalation. An attacker who successfully exploited this vulnerability could run arbitrary code in kernel mode.

Required action

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

Notes

https://msrc.microsoft.com/update-guide/en-US/advisory/CVE-2018-8639 ; https://nvd.nist.gov/vuln/detail/CVE-2018-8639

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