CVEs / CVE-2025-21391
CVE-2025-21391: Microsoft Windows Storage Link Following Vulnerability
- Known exploited in the CISA KEV catalog since 11 Feb 2025
- high 7.1 CVSS 3.1 (from the CNA)
- EPSS 2.28% chance of exploitation in the next 30 days, higher than 83% of CVEs (30 Oct 2026)
- Last changed at its sources
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Summary
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.
Description
Windows Storage Elevation of Privilege Vulnerability
Affected and fixed versions
| Product | Affected | Fixed in |
|---|---|---|
| Microsoft Windows 10 Version 1507 | from 10.0.10240.0, before 10.0.10240.20915 | 10.0.10240.20915 |
| Microsoft Windows 10 Version 1607 | from 10.0.14393.0, before 10.0.14393.7785 | 10.0.14393.7785 |
| Microsoft Windows 10 Version 1809 | from 10.0.17763.0, before 10.0.17763.6893 | 10.0.17763.6893 |
| Microsoft Windows 10 Version 21H2 | from 10.0.19044.0, before 10.0.19044.5487 | 10.0.19044.5487 |
| Microsoft Windows 10 Version 22H2 | from 10.0.19045.0, before 10.0.19045.5487 | 10.0.19045.5487 |
| Microsoft Windows 11 version 22H2 | from 10.0.22621.0, before 10.0.22621.4890 | 10.0.22621.4890 |
| Microsoft Windows 11 version 22H3 | from 10.0.22631.0, before 10.0.22631.4890 | 10.0.22631.4890 |
| Microsoft Windows 11 Version 23H2 | from 10.0.22631.0, before 10.0.22631.4890 | 10.0.22631.4890 |
| Microsoft Windows 11 Version 24H2 | from 10.0.26100.0, before 10.0.26100.3194 | 10.0.26100.3194 |
| Microsoft Windows Server 2016 | from 10.0.14393.0, before 10.0.14393.7785 | 10.0.14393.7785 |
| Microsoft Windows Server 2016 (Server Core installation) | from 10.0.14393.0, before 10.0.14393.7785 | 10.0.14393.7785 |
| Microsoft Windows Server 2019 | from 10.0.17763.0, before 10.0.17763.6893 | 10.0.17763.6893 |
| Microsoft Windows Server 2019 (Server Core installation) | from 10.0.17763.0, before 10.0.17763.6893 | 10.0.17763.6893 |
| Microsoft Windows Server 2022 | from 10.0.20348.0, before 10.0.20348.3207 | 10.0.20348.3207 |
| Microsoft Windows Server 2022, 23H2 Edition (Server Core installation) | from 10.0.25398.0, before 10.0.25398.1425 | 10.0.25398.1425 |
| Microsoft Windows Server 2025 | from 10.0.26100.0, before 10.0.26100.3194 | 10.0.26100.3194 |
| Microsoft Windows Server 2025 (Server Core installation) | from 10.0.26100.0, before 10.0.26100.3194 | 10.0.26100.3194 |
Exploitation
| In CISA KEV since | 11 Feb 2025 |
|---|---|
| Due date for US federal agencies | 4 Mar 2025 |
| Used in ransomware campaigns | Unknown |
| Required action | Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable. |
Severity
| CVSS 3.1 | 7.1 highCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:HScored by the CNA ([email protected]) |
|---|---|
| Weakness | CWE-59 |
References
- CVE-2025-21391 on NVD
- CVE-2025-21391 in the CISA KEV catalog
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-21391 (cited by CISA)
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-21391 Patch, Vendor Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-21391 US Government Resource
Sources
Exploitation status from the CISA Known Exploited Vulnerabilities catalog. EPSS scores from FIRST. Descriptions, severity and references from the National Vulnerability Database. Open-source package versions from OSV (CC-BY 4.0). Text is shown as each source states it; Stackurity does not edit it. Check the vendor's advisory before acting.
This product uses data from the NVD API but is not endorsed or certified by the NVD.