Microsoft Windows
YES - ON THE CISA KEV LIST
CVE-2018-8639
Microsoft Windows Win32k Improper Resource Shutdown or Release Vulnerability
overdue since 2025-03-24
Microsoft: 391 entries (22.0% of all KEV entries are from this vendor); 41 added in 2026.
BOD 26-04 note: this is the date printed in the CISA catalog. A federal agency's actual deadline is set by its SSVC tier - Act (3 days), Attend (14 days), Track (60 days), or the next scheduled upgrade - counted from the KEV listing date or the date the vulnerability is identified in its environment, whichever comes first. Use the tier helper on each CVE page for your own window.
Your BOD 26-04 window (SSVC tier helper)
Your remediation window ends:
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 (CISA)
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
References
Other KEV entries for this vendor: Microsoft
- CVE-2026-124194 - Office (2026-11-10)
- CVE-2026-96951 - Windows (2026-10-13)
- CVE-2026-65660 - SharePoint (2026-09-25)
- CVE-2026-81963 - Windows (2026-09-08)
- CVE-2026-85880 - Windows (2026-09-08)
- CVE-2019-1068 - SQL Server (2026-08-26)
- CVE-2026-33824 - Internet Key Exchange (IKE) Service Extensions (2026-08-18)
- CVE-2026-55040 - SharePoint (2026-08-18)
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