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CVE-2021-43226: Microsoft Windows Privilege Escalation Vulnerability
Microsoft Windows · in CISA KEV since 2025-10-06
2025-10-06added to KEV
2025-10-27federal remediation due date
3.07%EPSS exploit probability (30 days) 87.1th percentile
7.8 HIGHCVSS 3.1
Knownknown ransomware use
1,391days from NVD publication to KEV
What it is
Microsoft Windows Common Log File System Driver contains a privilege escalation vulnerability that could allow a local, privileged attacker to bypass certain security mechanisms.
Required action (CISA)
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
| CWE | — |
|---|---|
| CVSS vector | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| NVD published | 2021-12-15 (Analyzed) |
Original records: NVD · CISA KEV · JSON: /api/cve/CVE-2021-43226.json · all KEV CVEs
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Get the full file: Exploited Vulnerabilities Brief – September 2026 ($29): this month's KEV additions ranked by EPSS, ransomware use and due date, ready to hand to a patch team. Checkout by Polar.
Get the full file: Exploited Vulnerabilities Brief – September 2026 ($29): this month's KEV additions ranked by EPSS, ransomware use and due date, ready to hand to a patch team. Checkout by Polar.