{"id":"CVE-2026-40402","aliases":["EUVD-2026-29663","GHSA-h659-hh52-mv97"],"status":"published","title":"Windows Hyper-V Elevation of Privilege Vulnerability","description":"Use after free in Windows Hyper-V allows an unauthorized attacker to elevate privileges locally.","severity":{"version":"3.1","score":9.3,"vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H/E:U/RL:O/RC:C","level":"critical","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-11","score":0.00332,"percentile":0.26804,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-416"],"published":"2026-05-12T16:59:25Z","modified":"2026-08-10T15:13:34Z","products":[{"vendor":"microsoft","product":"windows 11 version 23h2"},{"vendor":"microsoft","product":"windows server 2022"},{"vendor":"microsoft","product":"windows_11_23h2"},{"vendor":"microsoft","product":"windows_server_2022"}],"references":[{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-40402","tags":["vendor-advisory","patch","Vendor Advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-40402"},{"url":"https://github.com/advisories/GHSA-h659-hh52-mv97"}],"sources":{"cve":[{"id":"CVE-2026-40402","title":"Windows Hyper-V Elevation of Privilege Vulnerability","description":"Use after free in Windows Hyper-V allows an unauthorized attacker to elevate privileges locally.","status":"published","published":"2026-05-12T16:59:25.931Z","modified":"2026-08-10T15:13:34.149Z","cvss":[{"version":"3.1","score":9.3,"vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H/E:U/RL:O/RC:C","level":"critical","assessor":"cna"}],"cwes":["CWE-416"],"updated_at":"2026-11-02T13:43:11.445168Z"}],"euvd":[{"id":"EUVD-2026-29663","description":"Use after free in Windows Hyper-V allows an unauthorized attacker to elevate privileges locally.","status":"published","published":"2026-05-12T16:59:25Z","modified":"2026-08-10T15:13:34Z","cvss":[{"version":"3.1","score":9.3,"vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H/E:U/RL:O/RC:C","level":"critical"}],"updated_at":"2026-11-02T18:02:02.39155Z"}],"ghsa":[{"id":"GHSA-h659-hh52-mv97","title":"Use after free in Windows Hyper-V allows an unauthorized attacker to elevate privileges locally.","description":"Use after free in Windows Hyper-V allows an unauthorized attacker to elevate privileges locally.","status":"published","published":"2026-05-12T18:30:45Z","modified":"2026-05-12T18:30:51Z","cvss":[{"version":"3.1","score":9.3,"vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H","level":"critical"}],"cwes":["CWE-416"],"updated_at":"2026-11-02T15:08:05.647564Z"}],"nvd":[{"id":"CVE-2026-40402","description":"Use after free in Windows Hyper-V allows an unauthorized attacker to elevate privileges locally.","status":"published","published":"2026-05-12T18:17:18Z","modified":"2026-06-17T10:45:15.21Z","cvss":[{"version":"3.1","score":9.3,"vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H","level":"critical","assessor":"secondary"}],"cwes":["CWE-416"],"updated_at":"2026-11-02T14:12:18.613259Z"}]}}