Microsoft Windows
YES - ON THE CISA KEV LIST
CVE-2025-21391
Microsoft Windows Storage Link Following Vulnerability
overdue since 2025-03-04
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 Storage contains a link following vulnerability that could allow for privilege escalation. This vulnerability could allow an attacker to delete data including data that results in the service being unavailable.
Required action (CISA)
Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
Notes
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-21391 ; https://nvd.nist.gov/vuln/detail/CVE-2025-21391
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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