CVE-2026-26177 json
Windows Ancillary Function Driver for WinSock Elevation of Privilege Vulnerability
published 2026-04-14 6 mo ago modified 2026-10-26 13 d ago also EUVD-2026-22416
- cvss
- 7.0
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.2%
- EPSS 0.2% chance of exploitation in 30 days, percentile 10%
- public exploits
- 0
- none known
Summary
Use after free in Windows Ancillary Function Driver for WinSock allows an authorized attacker to elevate privileges locally.
Patch / fix
- Microsoft Windows 10 Version 1607 10.0.14393.9060
- Microsoft Windows 10 Version 1809 10.0.17763.8644
- Microsoft Windows 10 Version 21H2 10.0.19044.7184
- Microsoft Windows 10 Version 22H2 10.0.19045.7184
- Microsoft Windows 11 version 23H2 10.0.22631.6936
- Microsoft Windows 11 Version 24H2 10.0.26100.8246
- Microsoft Windows 11 Version 25H2 10.0.26200.8246
- Microsoft Windows 11 version 26H1 10.0.28000.1836
- Microsoft Windows Server 2012 6.2.9200.26026
- Microsoft Windows Server 2012 (Server Core installation) 6.2.9200.26026
- Microsoft Windows Server 2012 R2 6.3.9600.23132
- Microsoft Windows Server 2012 R2 (Server Core installation) 6.3.9600.23132
- Microsoft Windows Server 2016 10.0.14393.9060
- Microsoft Windows Server 2016 (Server Core installation) 10.0.14393.9060
- Microsoft Windows Server 2019 10.0.17763.8644
- Microsoft Windows Server 2019 (Server Core installation) 10.0.17763.8644
- Microsoft Windows Server 2022 10.0.20348.5020
- Microsoft Windows Server 2022, 23H2 Edition (Server Core installation) 10.0.25398.2274
- Microsoft Windows Server 2025 10.0.26100.32690
- Microsoft Windows Server 2025 (Server Core installation) 10.0.26100.32690
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- total
- Assessed
- 6 mo ago
Exploit prediction
0.20% chance of exploitation in the next 30 days, higher than 10% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 7.0 | CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C |
| CNA | 3.1 | 7.0 | CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H |
Affected products
- Microsoft Windows 10 Version 1607
- Microsoft Windows 10 Version 1809
- Microsoft Windows 10 Version 21H2
- Microsoft Windows 10 Version 22H2
- Microsoft Windows 11 version 23H2
- Microsoft Windows 11 Version 24H2
- Microsoft Windows 11 Version 25H2
- Microsoft Windows 11 version 26H1
- 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-416 Use After Free
References
-
msrc.microsoft.com
/update-guide/vulnerability/CVE-2026-26177
vendor-advisory, patch
Sources
- CVE List CVE-2026-26177
- NVD CVE-2026-26177
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.