CVE-2025-21391
Microsoft Windows Storage contains a link following vulnerability that could allow for privilege escalation. This vulnerability could allow an…
Browse: All 2025 CVEs · All vendors
- CVSS score
- 7.1 High
- CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H- CISA KEV
- Yes — actively exploited (added 2025-02-11, remediation due 2025-03-04)
- Weakness (CWE)
- CWE-59
- Published
- 2025-02-11
- Last modified
- 2026-06-17
- NVD status
- Analyzed
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.
Affected products
- microsoft windows 10 1507
- microsoft windows 10 1607
- microsoft windows 10 1809
- microsoft windows 10 21h2
- microsoft windows 10 22h2
- microsoft windows 11 22h2
- microsoft windows 11 23h2
- microsoft windows 11 24h2
- microsoft windows server 2016
- microsoft windows server 2019
- microsoft windows server 2022
- microsoft windows server 2022 23h2
Affected ranges per NVD CPE data; confirm exact versions in the vendor advisory.
Required action (CISA)
Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable. Federal remediation deadline: 2025-03-04.
How to prioritize this
This vulnerability is on the CISA KEV list, meaning it is being actively exploited — treat it as urgent regardless of the raw CVSS number. Use the live CVE lookup for the latest NVD data, and the CVSS 3.1 calculator to model your own environmental score.
References
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-21391
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-21391
FAQ
Is CVE-2025-21391 actively exploited?
Yes. CISA added CVE-2025-21391 to its Known Exploited Vulnerabilities (KEV) catalog on 2025-02-11, with a federal remediation deadline of 2025-03-04. A KEV listing means real-world exploitation is confirmed, so patching this should be prioritized above many higher-CVSS bugs that aren't being exploited.
What is the CVSS score of CVE-2025-21391?
CVE-2025-21391 has a CVSS base score of 7.1 (High). Its vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H.
Related vulnerabilities
- CVE-2008-4250 — Microsoft Windows
- CVE-2026-32202 — Microsoft Windows
- CVE-2025-60710 — Microsoft Windows
- CVE-2023-36424 — Microsoft Windows
- CVE-2008-0015 — Microsoft Windows
- CVE-2026-21513 — Microsoft Windows
Data source: NVD & CISA KEV. Shown as-is; nothing added. Last generated from NVD data — re-check the live tool for updates.
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