SYSTEM code execution via heap buffer overflow
Published Jun 8, 2021 · Updated Aug 3, 2024
Heap-based buffer overflow in the Microsoft Windows Common Log File System driver allows local users to execute code as SYSTEM. The clfs.sys driver copies user-supplied data into a heap buffer without first validating its length. Exploitation requires the ability to run low-privileged code locally and grants complete control in the SYSTEM context.
Summary
What happened
Heap-based buffer overflow in the Microsoft Windows Common Log File System driver allows local users to execute code as SYSTEM. The clfs.sys driver copies user-supplied data into a heap buffer without first validating its length. Exploitation requires the ability to run low-privileged code locally and grants complete control in the SYSTEM context.
The record
- CVE
- CVE-2021-31954
- Published
- Jun 8, 2021
- Updated
- Aug 3, 2024
- Vendor
- Microsoft
- Product
- Windows 10 Version 1507
- Classifications
- CWE-122, CWE-269, T1068
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Jun 8, 2021CVE publishedPublication date reported by the CVE source.
- Aug 3, 2024Record 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=10.0.0 <10.0.10240.18967
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.
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Technologies
Your stack
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Your stack
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