CVE-2025-21418
HIGHCVSS 7.8/10Actively ExploitedEPSS 1.46%
Last modified
CVE-2025-21418 is a high-severity vulnerability rated 7.8/10 on the CVSS scale. Windows Ancillary Function Driver for WinSock Elevation of Privilege Vulnerability. CISA has confirmed active exploitation in the wild. EPSS estimates a 1.46% chance of exploitation in the next 30 days.
Description
Windows Ancillary Function Driver for WinSock Elevation of Privilege Vulnerability
Metrics
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Exploitation Status
This vulnerability is listed in CISA’s Known Exploited Vulnerabilities catalog, confirming active exploitation in the wild. Federal agencies must remediate by .
Weakness Enumeration
Affected Software
| Vendor | Product | Versions | Update |
|---|---|---|---|
| Microsoft | Windows 10 1607 | < 10.0.10240.20915 | — |
| Microsoft | Windows 10 1809 | < 10.0.17763.6893 | — |
| Microsoft | Windows 10 21h2 | < 10.0.19044.5487 | — |
| Microsoft | Windows 10 22h2 | < 10.0.19045.5487 | — |
| Microsoft | Windows 11 22h2 | < 10.0.22621.4890 | — |
| Microsoft | Windows 11 23h2 | < 10.0.22631.4890 | — |
| Microsoft | Windows 11 24h2 | < 10.0.26100.3107 | — |
| Microsoft | Windows Server 2008 | All versions | Sp2 |
| Microsoft | Windows Server 2008 | r2 | Sp1 |
| Microsoft | Windows Server 2012 | All versions | — |
| Microsoft | Windows Server 2012 | r2 | — |
| Microsoft | Windows Server 2016 | < 10.0.14393.7785 | — |
| Microsoft | Windows Server 2019 | < 10.0.17763.6893 | — |
| Microsoft | Windows Server 2022 | < 10.0.20348.3148 | — |
| Microsoft | Windows Server 2022 23h2 | < 10.0.25398.1425 | — |
| Microsoft | Windows Server 2025 | < 10.0.26100.3107 | — |
References
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-21418Patch, Vendor Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-21418US Government Resource
Timeline
- Published
- Last Modified
- Status
- Analyzed
Frequently Asked Questions
What is CVE-2025-21418?
Windows Ancillary Function Driver for WinSock Elevation of Privilege Vulnerability
How severe is CVE-2025-21418?
CVE-2025-21418 has a CVSS score of 7.8/10 (HIGH severity). The EPSS model estimates a 1.46% probability of exploitation in the next 30 days. This vulnerability is listed in CISA's Known Exploited Vulnerabilities catalog.
How do I fix CVE-2025-21418?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.
Are you affected by CVE-2025-21418?
Run a free Strix scan to check your systems for this vulnerability.
Scan your code nowSource: NVD / NIST