{"id":"CVE-2026-85858","aliases":["EUVD-2026-99563","GHSA-3rq5-w539-p23v"],"status":"published","title":"Windows Win32 Kernel Subsystem Elevation of Privilege Vulnerability","description":"Out-of-bounds read in Windows Win32 Kernel Subsystem allows an authorized attacker to elevate privileges locally.","severity":{"version":"3.1","score":7.8,"vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H/E:U/RL:O/RC:C","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-13","score":0.00246,"percentile":0.15964,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-125"],"published":"2026-10-13T19:00:09Z","modified":"2026-11-10T20:38:22Z","products":[{"vendor":"microsoft","product":"windows 11 version 23h2"},{"vendor":"microsoft","product":"windows 11 version 24h2"},{"vendor":"microsoft","product":"windows 11 version 25h2"},{"vendor":"microsoft","product":"windows 11 version 26h1"},{"vendor":"microsoft","product":"windows 11 version 26h2"},{"vendor":"microsoft","product":"windows server 2022"},{"vendor":"microsoft","product":"windows server 2025"},{"vendor":"microsoft","product":"windows server 2025 (server core installation)"},{"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_11_26h2"},{"vendor":"microsoft","product":"windows_server_2022"},{"vendor":"microsoft","product":"windows_server_2025"}],"references":[{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-85858","tags":["vendor-advisory","patch","Patch","Vendor Advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-85858"},{"url":"https://github.com/advisories/GHSA-3rq5-w539-p23v"}],"sources":{"cve":[{"id":"CVE-2026-85858","title":"Windows Win32 Kernel Subsystem Elevation of Privilege Vulnerability","description":"Out-of-bounds read in Windows Win32 Kernel Subsystem allows an authorized attacker to elevate privileges locally.","status":"published","published":"2026-10-13T19:00:09.724Z","modified":"2026-11-10T20:38:22.279Z","cvss":[{"version":"3.1","score":7.8,"vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H/E:U/RL:O/RC:C","level":"high","assessor":"cna"}],"cwes":["CWE-125"],"updated_at":"2026-11-10T22:18:29.471829Z"}],"euvd":[{"id":"EUVD-2026-99563","description":"Out-of-bounds read in Windows Win32 Kernel Subsystem allows an authorized attacker to elevate privileges locally.","status":"published","published":"2026-10-13T19:00:09Z","modified":"2026-11-10T20:38:22Z","cvss":[{"version":"3.1","score":7.8,"vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H/E:U/RL:O/RC:C","level":"high"}],"updated_at":"2026-11-10T22:23:59.503929Z"}],"ghsa":[{"id":"GHSA-3rq5-w539-p23v","title":"Out-of-bounds read in Windows Win32 Kernel Subsystem allows an authorized attacker to elevate...","description":"Out-of-bounds read in Windows Win32 Kernel Subsystem allows an authorized attacker to elevate privileges locally.","status":"published","published":"2026-10-13T21:36:07Z","modified":"2026-10-13T21:36:08Z","cvss":[{"version":"3.1","score":7.8,"vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H","level":"high"}],"cwes":["CWE-125"],"updated_at":"2026-11-02T15:13:17.952607Z"}],"nvd":[{"id":"CVE-2026-85858","description":"Out-of-bounds read in Windows Win32 Kernel Subsystem allows an authorized attacker to elevate privileges locally.","status":"published","published":"2026-10-13T19:21:12.41Z","modified":"2026-10-29T19:36:29.76Z","cvss":[{"version":"3.1","score":7.8,"vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H","level":"high","assessor":"secondary"}],"cwes":["CWE-125"],"updated_at":"2026-11-02T14:12:58.13117Z"}]}}