CVE-2026-20810 (GCVE-0-2026-20810)

Vulnerability from cvelistv5 – Published: 2026-01-13 17:56 – Updated: 2026-02-22 17:00
VLAI?
Title
Windows Ancillary Function Driver for WinSock Elevation of Privilege Vulnerability
Summary
Free of memory not on the heap in Windows Ancillary Function Driver for WinSock allows an authorized attacker to elevate privileges locally.
Severity ?
7.8 (High)
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
CWE
  • CWE-590 - Free of Memory not on the Heap
Assigner
References
Impacted products
Vendor Product Version
Microsoft Windows 10 Version 1809 Affected: 10.0.17763.0 , < 10.0.17763.8276 (custom)
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    Microsoft Windows 10 Version 21H2 Affected: 10.0.19044.0 , < 10.0.19044.6809 (custom)
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    Microsoft Windows 10 Version 22H2 Affected: 10.0.19045.0 , < 10.0.19045.6809 (custom)
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    Microsoft Windows Server 2019 Affected: 10.0.17763.0 , < 10.0.17763.8276 (custom)
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    Microsoft Windows Server 2019 (Server Core installation) Affected: 10.0.17763.0 , < 10.0.17763.8276 (custom)
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Sightings

Author Source Type Date

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



Detection rules are retrieved from Rulezet.