CVE-2025-21418 kev in the critical feed json
Windows Ancillary Function Driver for WinSock Elevation of Privilege Vulnerability
published 2025-02-11 20 mo ago modified 2026-06-17 4 mo ago also EUVD-2025-2476
- cvss
- 7.8
- version 3.1, CNA
- cisa kev
- Exploited
- added 2025-02-11
- epss
- 2.1%
- EPSS 2.1% chance of exploitation in 30 days, percentile 82%
- public exploits
- 0
- none known
Summary
Windows Ancillary Function Driver for WinSock Elevation of Privilege Vulnerability
Patch / fix
cisa required action Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
- Microsoft Windows 10 Version 1507 10.0.10240.20915
- Microsoft Windows 10 Version 1607 10.0.14393.7785
- Microsoft Windows 10 Version 1809 10.0.17763.6893
- Microsoft Windows 10 Version 21H2 10.0.19044.5487
- Microsoft Windows 10 Version 22H2 10.0.19045.5487
- Microsoft Windows 11 version 22H2 10.0.22621.4890
- Microsoft Windows 11 version 22H3 10.0.22631.4890
- Microsoft Windows 11 Version 23H2 10.0.22631.4890
- Microsoft Windows 11 Version 24H2 10.0.26100.3194
- Microsoft Windows Server 2008 R2 Service Pack 1 6.1.7601.27566
- Microsoft Windows Server 2008 R2 Service Pack 1 (Server Core installation) 6.1.7601.27566
- Microsoft Windows Server 2008 Service Pack 2 6.0.6003.23117
- Microsoft Windows Server 2008 Service Pack 2 (Server Core installation) 6.0.6003.23117
- Microsoft Windows Server 2012 6.2.9200.25317
- Microsoft Windows Server 2012 (Server Core installation) 6.2.9200.25317
- Microsoft Windows Server 2012 R2 6.3.9600.22417
- Microsoft Windows Server 2012 R2 (Server Core installation) 6.3.9600.22417
- Microsoft Windows Server 2016 10.0.14393.7785
- Microsoft Windows Server 2016 (Server Core installation) 10.0.14393.7785
- Microsoft Windows Server 2019 10.0.17763.6893
- Microsoft Windows Server 2019 (Server Core installation) 10.0.17763.6893
- Microsoft Windows Server 2022 10.0.20348.3207
- Microsoft Windows Server 2022, 23H2 Edition (Server Core installation) 10.0.25398.1425
- Microsoft Windows Server 2025 10.0.26100.3194
- Microsoft Windows Server 2025 (Server Core installation) 10.0.26100.3194
Timeline
- 0-day patched (Project Zero)
- Added to CISA KEV
- Published
- CISA SSVC: exploitation active
- CISA patch deadline
Known exploited
- Added
- 20 mo ago
- Patch by
- 2025-03-04 (20 mo ago)
- Ransomware
- Not known
- Required action
- Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
- Vendor, product
- Microsoft, Windows
- CISA name
- Microsoft Windows Ancillary Function Driver for WinSock Heap-Based Buffer Overflow Vulnerability
Zero-day
Detected in real attacks while still unknown to the vendor and the public, per Google Project Zero's 0day In-the-Wild tracker.
- Patched
- 2025-02-11
- Details
- project zero tracker
ATT&CK techniques
How it is exploited and what it leads to, in MITRE ATT&CK terms.
- T1068 Exploitation for Privilege Escalation exploitation
- T1005 Data from Local System primary impact
- T1055 Process Injection primary impact
kev release 2025-07-28, att&ck v16.1. KEV to ATT&CK mappings by the MITRE Center for Threat-Informed Defense (Mappings Explorer, Apache-2.0). © 2026 The MITRE Corporation. This work is reproduced and distributed with the permission of The MITRE Corporation. Terms of use
CISA SSVC
- Exploitation
- Active, exploited in the wild
- Automatable
- no
- Technical impact
- total
- Assessed
- 20 mo ago
Exploit prediction
2.13% chance of exploitation in the next 30 days, higher than 82% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:F/RL:O/RC:C |
| CNA | 3.1 | 7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
Affected products
- Microsoft Windows 10 Version 1507
- Microsoft Windows 10 Version 1607
- Microsoft Windows 10 Version 1809
- Microsoft Windows 10 Version 21H2
- Microsoft Windows 10 Version 22H2
- Microsoft Windows 11 version 22H2
- Microsoft Windows 11 version 22H3
- Microsoft Windows 11 Version 23H2
- Microsoft Windows 11 Version 24H2
- Microsoft Windows Server 2008 R2 Service Pack 1
- Microsoft Windows Server 2008 R2 Service Pack 1 (Server Core installation)
- Microsoft Windows Server 2008 Service Pack 2
- Microsoft Windows Server 2008 Service Pack 2 (Server Core installation)
- Microsoft Windows Server 2012
- Microsoft Windows Server 2012 (Server Core installation)
- Microsoft Windows Server 2012 R2
- Microsoft Windows Server 2012 R2 (Server Core installation)
- Microsoft Windows Server 2016
- Microsoft Windows Server 2016 (Server Core installation)
- Microsoft Windows Server 2019
- Microsoft Windows Server 2019 (Server Core installation)
- Microsoft Windows Server 2022
- Microsoft Windows Server 2022, 23H2 Edition (Server Core installation)
- Microsoft Windows Server 2025
- Microsoft Windows Server 2025 (Server Core installation)
Classification
- Weakness
-
- CWE-122 Heap-based Buffer Overflow
References
-
msrc.microsoft.com
/update-guide/vulnerability/CVE-2025-21418
vendor-advisory, patch
-
cisa.gov
/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-21418
government-resource, us-government-resource
Sources
- CVE List CVE-2025-21418
- NVD CVE-2025-21418
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.