Local privilege escalation via unchecked PEB lengths
Published Jul 10, 2026 · Updated Jul 10, 2026
Heap buffer overflow in osquery before 5.23.1 on Windows allows local users to write beyond a heap buffer through a crafted process. The processes table trusts attacker-controlled PEB lengths for command-line and current-directory strings and passes them to ReadProcessMemory without clamping them to the 8,192-byte destination. Exploitation requires a privileged processes-table query to inspect the malicious process and can elevate a standard user to SYSTEM.
Summary
What happened
Heap buffer overflow in osquery before 5.23.1 on Windows allows local users to write beyond a heap buffer through a crafted process. The processes table trusts attacker-controlled PEB lengths for command-line and current-directory strings and passes them to ReadProcessMemory without clamping them to the 8,192-byte destination. Exploitation requires a privileged processes-table query to inspect the malicious process and can elevate a standard user to SYSTEM.
The record
- CVE
- CVE-2026-54000
- Published
- Jul 10, 2026
- Updated
- Jul 10, 2026
- Vendor
- osquery
- Product
- osquery
- Classifications
- CWE-122, T1068
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Jul 10, 2026CVE publishedPublication date reported by the CVE source.
- Jul 10, 2026Record 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=< 5.23.1
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
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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