{"id":"CVE-2021-43226","aliases":["EUVD-2021-30170","GHSA-98jh-5xvm-p5ph"],"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":"2026-11-12","score":0.03275,"percentile":0.88598,"model":"v2026.06.15"},"facts":{"in_kev":true,"known_exploited":true,"public_exploit":true,"fix_available":false},"cwes":["CWE-269"],"published":"2021-12-15T14:15:12Z","modified":"2026-08-22T04:16:54Z","kev":{"date_added":"2025-10-06","due_date":"2025-10-27","required_action":"Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are 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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_1507"},{"vendor":"microsoft","product":"windows_10_1607"},{"vendor":"microsoft","product":"windows_10_1809"},{"vendor":"microsoft","product":"windows_10_1909"},{"vendor":"microsoft","product":"windows_10_2004"},{"vendor":"microsoft","product":"windows_10_20h2"},{"vendor":"microsoft","product":"windows_10_21h1"},{"vendor":"microsoft","product":"windows_10_21h2"},{"vendor":"microsoft","product":"windows_11_21h2"},{"vendor":"microsoft","product":"windows_7"},{"vendor":"microsoft","product":"windows_8.1"},{"vendor":"microsoft","product":"windows_rt_8.1"},{"vendor":"microsoft","product":"windows_server_2004"},{"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"},{"vendor":"microsoft","product":"windows_server_20h2"}],"references":[{"url":"https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-43226","tags":["x_refsource_MISC","x_transferred","Patch","Vendor Advisory"]},{"url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-43226","tags":["government-resource","US Government Resource"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-43226"},{"url":"https://github.com/advisories/GHSA-98jh-5xvm-p5ph"}],"sources":{"cve":[{"id":"CVE-2021-43226","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":"2021-12-15T14:15:12Z","modified":"2026-08-22T03:55:15.007Z","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":"2026-11-02T14:32:57.033395Z"}],"euvd":[{"id":"EUVD-2021-30170","description":"Windows Common Log File System Driver Elevation of Privilege 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Driver contains a privilege escalation vulnerability that could allow a local, privileged attacker to bypass certain security mechanisms.","kev":{"date_added":"2025-10-06","due_date":"2025-10-27","required_action":"Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.","known_ransomware_use":"Known"},"updated_at":"2026-11-02T17:00:15.999436Z"}],"nvd":[{"id":"CVE-2021-43226","description":"Windows Common Log File System Driver Elevation of Privilege 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