{"id":"CVE-2026-34345","aliases":["EUVD-2026-29604","GHSA-j2x4-j6jv-hpjv"],"status":"published","title":"Windows Ancillary Function Driver for WinSock Elevation of Privilege Vulnerability","description":"Access of resource using incompatible type ('type confusion') in Windows Ancillary Function Driver for WinSock allows an authorized attacker to elevate privileges locally.","severity":{"version":"3.1","score":7,"vector":"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","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-09","score":0.00204,"percentile":0.10439,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-362","CWE-416"],"published":"2026-05-12T16:58:25Z","modified":"2026-08-10T15:12:39Z","products":[{"vendor":"microsoft","product":"windows 10 version 1607"},{"vendor":"microsoft","product":"windows 10 version 1809"},{"vendor":"microsoft","product":"windows 10 version 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installation)"},{"vendor":"microsoft","product":"windows_10_1607"},{"vendor":"microsoft","product":"windows_10_1809"},{"vendor":"microsoft","product":"windows_10_21h2"},{"vendor":"microsoft","product":"windows_10_22h2"},{"vendor":"microsoft","product":"windows_11_23h2"},{"vendor":"microsoft","product":"windows_11_24h2"},{"vendor":"microsoft","product":"windows_11_25h2"},{"vendor":"microsoft","product":"windows_11_26h1"},{"vendor":"microsoft","product":"windows_server_2016"},{"vendor":"microsoft","product":"windows_server_2019"},{"vendor":"microsoft","product":"windows_server_2022"},{"vendor":"microsoft","product":"windows_server_2022_23h2"},{"vendor":"microsoft","product":"windows_server_2025"}],"references":[{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-34345","tags":["vendor-advisory","patch","Vendor Advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-34345"},{"url":"https://github.com/advisories/GHSA-j2x4-j6jv-hpjv"}],"sources":{"cve":[{"id":"CVE-2026-34345","title":"Windows Ancillary Function Driver for WinSock Elevation of Privilege Vulnerability","description":"Access of resource using incompatible type ('type confusion') in Windows Ancillary Function Driver for WinSock allows an authorized attacker to elevate privileges locally.","status":"published","published":"2026-05-12T16:58:25.988Z","modified":"2026-08-10T15:12:39.615Z","cvss":[{"version":"3.1","score":7,"vector":"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","level":"high","assessor":"cna"}],"cwes":["CWE-362","CWE-416"],"updated_at":"2026-11-02T14:20:14.665567Z"}],"euvd":[{"id":"EUVD-2026-29604","description":"Access of resource using incompatible type ('type confusion') in Windows Ancillary Function Driver for WinSock allows an authorized attacker to elevate privileges 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Windows Ancillary Function Driver for WinSock allows an authorized attacker to elevate privileges locally.","status":"published","published":"2026-05-12T18:17:09.19Z","modified":"2026-06-17T10:38:55.2Z","cvss":[{"version":"3.1","score":7,"vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H","level":"high","assessor":"secondary"}],"cwes":["CWE-362","CWE-416"],"updated_at":"2026-11-02T14:12:18.613259Z"}]}}