{"id":"CVE-2021-43226","url":"https://www.cyber-defence.io/tools/cve/CVE-2021-43226","generatedAt":"2026-10-31T14:01:54.908Z","title":"Microsoft Windows Privilege Escalation Vulnerability","description":"Windows Common Log File System Driver Elevation of Privilege Vulnerability","published":"2021-12-15T15:15:10.000Z","lastModified":"2026-08-22T04:16:55.000Z","status":"Analyzed","sourceIdentifier":"secure@microsoft.com","cvss":{"version":"3.1","score":7.8,"severity":"HIGH","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"},"cwe":[],"affected":["microsoft/windows 10 1507","microsoft/windows 10 1607","microsoft/windows 10 1809","microsoft/windows 10 1909","microsoft/windows 10 2004","microsoft/windows 10 20h2","microsoft/windows 10 21h1","microsoft/windows 10 21h2","microsoft/windows 11 21h2","microsoft/windows 7","microsoft/windows 8.1","microsoft/windows rt 8.1","microsoft/windows server 2004","microsoft/windows server 2008","microsoft/windows server 2012","microsoft/windows server 2016","microsoft/windows server 2019","microsoft/windows server 2022","microsoft/windows server 20h2"],"epss":{"score":0.03275,"percentile":0.88407,"date":"2026-10-30","history":[]},"kev":{"listed":true,"dateAdded":"2025-10-06","dueDate":"2025-10-27","knownRansomwareCampaignUse":"Known","notes":"Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.\nhttps://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-43226 ; https://nvd.nist.gov/vuln/detail/CVE-2021-43226"},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"urgent","text":"Known to be exploited in the wild (CISA KEV, CISA remediation deadline 27 October 2025). Treat as an emergency change: patch or isolate now, then hunt for prior compromise."},"changes":[],"references":[{"url":"https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-43226","tags":["Patch","Vendor Advisory"],"source":"secure@microsoft.com"},{"url":"https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-43226","tags":["Patch","Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-43226","tags":["US Government Resource"],"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2021-43226","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}