{"id":"CVE-2026-20810","aliases":["EUVD-2026-2194","GHSA-c77x-pfg5-gxc3"],"status":"published","title":"Windows Ancillary Function Driver for WinSock Elevation of Privilege Vulnerability","description":"Free of memory not on the heap in Windows Ancillary Function Driver for WinSock allows an authorized attacker to elevate privileges locally.","severity":{"version":"3.1","score":7.8,"vector":"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","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-11","score":0.00489,"percentile":0.42532,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-590"],"published":"2026-01-13T17:56:10Z","modified":"2026-07-30T20:46:28Z","products":[{"vendor":"microsoft","product":"windows 10 version 1809"},{"vendor":"microsoft","product":"windows 10 version 21h2"},{"vendor":"microsoft","product":"windows 10 version 22h2"},{"vendor":"microsoft","product":"windows server 2019"},{"vendor":"microsoft","product":"windows server 2019 (server core installation)"},{"vendor":"microsoft","product":"windows_10_1809"},{"vendor":"microsoft","product":"windows_10_21h2"},{"vendor":"microsoft","product":"windows_10_22h2"},{"vendor":"microsoft","product":"windows_server_2019"}],"references":[{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20810","tags":["vendor-advisory","patch","Vendor Advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-20810"},{"url":"https://github.com/advisories/GHSA-c77x-pfg5-gxc3"}],"sources":{"cve":[{"id":"CVE-2026-20810","title":"Windows Ancillary Function Driver for WinSock Elevation of Privilege Vulnerability","description":"Free of memory not on the heap in Windows Ancillary Function Driver for WinSock allows an authorized attacker to elevate privileges locally.","status":"published","published":"2026-01-13T17:56:10.446Z","modified":"2026-07-30T20:46:28.241Z","cvss":[{"version":"3.1","score":7.8,"vector":"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","level":"high","assessor":"cna"}],"cwes":["CWE-590"],"updated_at":"2026-11-02T13:35:33.380441Z"}],"euvd":[{"id":"EUVD-2026-2194","description":"Free of memory not on the heap in Windows Ancillary Function Driver for WinSock allows an authorized attacker to elevate privileges locally.","status":"published","published":"2026-01-13T17:56:10Z","modified":"2026-07-30T20:46:28Z","cvss":[{"version":"3.1","score":7.8,"vector":"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","level":"high"}],"updated_at":"2026-11-02T18:02:27.233735Z"}],"ghsa":[{"id":"GHSA-c77x-pfg5-gxc3","title":"Free of memory not on the heap in Windows Ancillary Function Driver for WinSock allows an...","description":"Free of memory not on the heap in Windows Ancillary Function Driver for WinSock allows an authorized attacker to elevate privileges locally.","status":"published","published":"2026-01-13T18:31:08Z","modified":"2026-01-13T18:31:14Z","cvss":[{"version":"3.1","score":7.8,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","level":"high"}],"cwes":["CWE-590"],"updated_at":"2026-11-02T15:05:35.156514Z"}],"nvd":[{"id":"CVE-2026-20810","description":"Free of memory not on the heap in Windows Ancillary Function Driver for WinSock allows an authorized attacker to elevate privileges locally.","status":"published","published":"2026-01-13T18:16:07.547Z","modified":"2026-06-17T10:17:49.373Z","cvss":[{"version":"3.1","score":7.8,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","level":"high","assessor":"secondary"}],"cwes":["CWE-590"],"updated_at":"2026-11-02T14:12:03.683495Z"}]}}