Microsoft Windows Privilege Escalation Vulnerability
Microsoft — Windows 10 Version 1809
Windows Common Log File System Driver Elevation of Privilege Vulnerability
7.8
3.1%
Vector breakdown
- Attack vector
- Local
- Attack complexity
- Low
- Privileges required
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- Published
- Dec 15, 2021
- Modified
- Aug 22, 2026
- Added to KEV
- Oct 6, 2025
- Federal patch due
- Oct 27, 2025
CISA 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.
Affected packages
Proof-of-concept & exploitation references
1 foundWeaponization
Public repositories whose name or description references CVE-2021-43226, found via a live GitHub search at request time. These are community-sourced signals, not a verified working exploit - cross-check each one before relying on it, and treat higher star counts and recent activity as (weak) corroboration, not proof.
References
Frequently asked questions
What is CVE-2021-43226?
Windows Common Log File System Driver Elevation of Privilege Vulnerability
How severe is CVE-2021-43226?
CVE-2021-43226 has a CVSS base score of 7.8 out of 10 (CVSS 3.1).
Is CVE-2021-43226 actively exploited in the wild?
Yes. CVE-2021-43226 is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog, added Oct 6, 2025, meaning CISA has confirmed evidence of active exploitation. It is also flagged as used in ransomware campaigns.
What is the EPSS score for CVE-2021-43226?
3.1% - meaning FIRST.org's EPSS model estimates a 3.1% probability this vulnerability will be exploited in the wild within 30 days (87% percentile among all scored CVEs).
Is there exploit tooling available for CVE-2021-43226?
We found 1 public GitHub repository referencing CVE-2021-43226, though none matched a known Nuclei template or Metasploit module at last check. Review each one before relying on it - see the proof-of-concept section above.
Cross-checked against
Impactr finds and proves whether CVE-2021-43226 - or flaws like it - are actually reachable in your own web apps and APIs, with a reproducible exploit as evidence.
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