CVE-2026-20810 json
Windows Ancillary Function Driver for WinSock Elevation of Privilege Vulnerability
published 2026-01-13 9 mo ago modified 2026-07-30 3 mo ago also EUVD-2026-2194
- cvss
- 7.8
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.5%
- EPSS 0.5% chance of exploitation in 30 days, percentile 42%
- public exploits
- 0
- none known
Summary
Free of memory not on the heap in Windows Ancillary Function Driver for WinSock allows an authorized attacker to elevate privileges locally.
Patch / fix
- Microsoft Windows 10 Version 1809 10.0.17763.8276
- Microsoft Windows 10 Version 21H2 10.0.19044.6809
- Microsoft Windows 10 Version 22H2 10.0.19045.6809
- Microsoft Windows Server 2019 10.0.17763.8276
- Microsoft Windows Server 2019 (Server Core installation) 10.0.17763.8276
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- total
- Assessed
- 9 mo ago
Exploit prediction
0.49% chance of exploitation in the next 30 days, higher than 42% 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:U/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 1809
- Microsoft Windows 10 Version 21H2
- Microsoft Windows 10 Version 22H2
- Microsoft Windows Server 2019
- Microsoft Windows Server 2019 (Server Core installation)
Classification
- Weakness
-
- CWE-590 Free of Memory not on the Heap
References
-
msrc.microsoft.com
/update-guide/vulnerability/CVE-2026-20810
vendor-advisory, patch
Sources
- CVE List CVE-2026-20810
- NVD CVE-2026-20810
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