Kernel privilege escalation via crafted BLF file
Published Sep 12, 2023 · Updated Oct 30, 2025
Buffer over-read in the Common Log File System driver in Microsoft Windows allows local users to elevate privileges through a crafted BLF file. The clfs.sys driver reads past the end of an allocated buffer while parsing the malicious log file, exposing kernel memory. Low-privileged code execution on the target is required; the disclosure can be chained with another flaw to execute code in the kernel context.
Summary
What happened
Buffer over-read in the Common Log File System driver in Microsoft Windows allows local users to elevate privileges through a crafted BLF file. The clfs.sys driver reads past the end of an allocated buffer while parsing the malicious log file, exposing kernel memory. Low-privileged code execution on the target is required; the disclosure can be chained with another flaw to execute code in the kernel context.
The record
- CVE
- CVE-2023-38144
- Published
- Sep 12, 2023
- Updated
- Oct 30, 2025
- Vendor
- Microsoft
- Product
- Windows 10 Version 1507
- Classifications
- CWE-126, 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
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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
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Attacks
What attackers are doing with it
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Public exploit references
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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