SYSTEM code execution via named pipe squatting
Published Feb 25, 2021 · Updated Nov 19, 2024
Local privilege escalation in Microsoft PsExec 2.32 and earlier allows local users to execute arbitrary code as SYSTEM on Windows. PSEXESVC.EXE creates its command pipe without ensuring that it owns the first instance, so the SYSTEM service reopens an attacker-created PSEXESVC pipe and accepts malicious process-launch instructions. Exploitation requires existing low-privilege code execution on a Windows host while an administrator invokes PsExec against that host.
Summary
What happened
Local privilege escalation in Microsoft PsExec 2.32 and earlier allows local users to execute arbitrary code as SYSTEM on Windows. PSEXESVC.EXE creates its command pipe without ensuring that it owns the first instance, so the SYSTEM service reopens an attacker-created PSEXESVC pipe and accepts malicious process-launch instructions. Exploitation requires existing low-privilege code execution on a Windows host while an administrator invokes PsExec against that host.
The record
- CVE
- CVE-2021-1733
- Published
- Feb 25, 2021
- Updated
- Nov 19, 2024
- Vendor
- Microsoft
- Product
- PsExec
- Classifications
- CWE-269, T1068
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Feb 25, 2021CVE publishedPublication date reported by the CVE source.
- Nov 19, 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?
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- Affected versionversion=0 <publication
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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Weakness, pattern, technique
Public exploit references
- PsExecEscalate proof of conceptproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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