Local privilege escalation via CLFS heap overflow
Published Sep 12, 2023 · Updated Oct 30, 2025
A heap-based buffer overflow in the Windows Common Log File System driver allows local users to elevate privileges on affected Windows builds. Microsoft has not disclosed the function, parsing path, or specific operation that overwrites the heap buffer. Exploitation requires local low-privilege access and can yield control at SYSTEM level without user interaction or network exposure.
Summary
What happened
A heap-based buffer overflow in the Windows Common Log File System driver allows local users to elevate privileges on affected Windows builds. Microsoft has not disclosed the function, parsing path, or specific operation that overwrites the heap buffer. Exploitation requires local low-privilege access and can yield control at SYSTEM level without user interaction or network exposure.
The record
- CVE
- CVE-2023-38143
- Published
- Sep 12, 2023
- Updated
- Oct 30, 2025
- Vendor
- Microsoft
- Product
- Windows 10 Version 1507
- Classifications
- CWE-122, T1068
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Sep 12, 2023CVE publishedPublication date reported by the CVE source.
- Oct 30, 2025Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=10.0.10240.0 <10.0.10240.20162
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
No public exploit references are available in this record.
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo