{"id":"CVE-2021-40466","aliases":["EUVD-2021-27643","GHSA-h4jc-qmgp-cjpv"],"status":"published","title":"Windows Common Log File System Driver Elevation of Privilege Vulnerability","description":"Windows Common Log File System Driver Elevation of Privilege Vulnerability","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":"2026-11-09","score":0.00651,"percentile":0.51499,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-269"],"published":"2021-10-13T00:27:06Z","modified":"2026-06-17T04:06:58Z","products":[{"vendor":"microsoft","product":"windows 10 version 1507"},{"vendor":"microsoft","product":"windows 10 version 1607"},{"vendor":"microsoft","product":"windows 10 version 1809"},{"vendor":"microsoft","product":"windows 10 version 1909"},{"vendor":"microsoft","product":"windows 10 version 2004"},{"vendor":"microsoft","product":"windows 10 version 20h2"},{"vendor":"microsoft","product":"windows 10 version 21h1"},{"vendor":"microsoft","product":"windows 11 version 21h2"},{"vendor":"microsoft","product":"windows 7"},{"vendor":"microsoft","product":"windows 7 service pack 1"},{"vendor":"microsoft","product":"windows 8.1"},{"vendor":"microsoft","product":"windows server 2008  service pack 2"},{"vendor":"microsoft","product":"windows server 2008 r2 service pack 1"},{"vendor":"microsoft","product":"windows server 2008 r2 service pack 1 (server core installation)"},{"vendor":"microsoft","product":"windows server 2008 service pack 2"},{"vendor":"microsoft","product":"windows server 2008 service pack 2 (server core installation)"},{"vendor":"microsoft","product":"windows server 2012"},{"vendor":"microsoft","product":"windows server 2012 (server core installation)"},{"vendor":"microsoft","product":"windows server 2012 r2"},{"vendor":"microsoft","product":"windows server 2012 r2 (server core installation)"},{"vendor":"microsoft","product":"windows server 2016"},{"vendor":"microsoft","product":"windows server 2016 (server core installation)"},{"vendor":"microsoft","product":"windows server 2019"},{"vendor":"microsoft","product":"windows server 2019 (server core installation)"},{"vendor":"microsoft","product":"windows server 2022"},{"vendor":"microsoft","product":"windows server version 2004"},{"vendor":"microsoft","product":"windows server version 20h2"},{"vendor":"microsoft","product":"windows_10"},{"vendor":"microsoft","product":"windows_11"},{"vendor":"microsoft","product":"windows_7"},{"vendor":"microsoft","product":"windows_8.1"},{"vendor":"microsoft","product":"windows_rt_8.1"},{"vendor":"microsoft","product":"windows_server_2008"},{"vendor":"microsoft","product":"windows_server_2012"},{"vendor":"microsoft","product":"windows_server_2016"},{"vendor":"microsoft","product":"windows_server_2019"},{"vendor":"microsoft","product":"windows_server_2022"}],"references":[{"url":"https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-40466","tags":["x_refsource_MISC","x_transferred","Patch","Vendor Advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-40466"},{"url":"https://github.com/advisories/GHSA-h4jc-qmgp-cjpv"}],"sources":{"cve":[{"id":"CVE-2021-40466","title":"Windows Common Log File System Driver Elevation of Privilege Vulnerability","description":"Windows Common Log File System Driver Elevation of Privilege Vulnerability","status":"published","published":"2021-10-13T00:27:06Z","modified":"2024-08-04T02:44:10.335Z","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"}],"updated_at":"2026-11-02T14:33:01.852999Z"}],"euvd":[{"id":"EUVD-2021-27643","description":"Windows Common Log File System Driver Elevation of Privilege Vulnerability","status":"published","published":"2021-10-13T00:27:06Z","modified":"2024-08-04T02:44:10Z","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":"2026-11-03T03:24:20.862157Z"}],"ghsa":[{"id":"GHSA-h4jc-qmgp-cjpv","title":"Windows Common Log File System Driver Elevation of Privilege Vulnerability This CVE ID is unique...","description":"Windows Common Log File System Driver Elevation of Privilege Vulnerability This CVE ID is unique from CVE-2021-40443, CVE-2021-40467.","status":"published","published":"2022-05-24T19:17:31Z","modified":"2023-08-10T05:04:48Z","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-269"],"updated_at":"2026-11-02T14:54:44.654498Z"}],"nvd":[{"id":"CVE-2021-40466","description":"Windows Common Log File System Driver Elevation of Privilege Vulnerability","status":"published","published":"2021-10-13T01:15:10.613Z","modified":"2026-06-17T04:06:58.583Z","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"},{"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"},{"version":"2.0","score":4.6,"vector":"AV:L/AC:L/Au:N/C:P/I:P/A:P","level":"medium","assessor":"primary"}],"cwes":["CWE-269"],"updated_at":"2026-11-02T14:06:59.689345Z"}]}}