Remote code execution via L2TP use-after-free
Published Jan 10, 2023 · Updated Jan 1, 2025
Use-after-free in Windows L2TP allows remote attackers to execute arbitrary code by sending crafted requests to a RAS server. The L2TP handler can access freed memory while processing concurrent connection requests, creating an attacker-controlled race. The target must act as a RAS server, and exploitation requires preparatory actions and winning the race; success runs code on that server.
Summary
What happened
Use-after-free in Windows L2TP allows remote attackers to execute arbitrary code by sending crafted requests to a RAS server. The L2TP handler can access freed memory while processing concurrent connection requests, creating an attacker-controlled race. The target must act as a RAS server, and exploitation requires preparatory actions and winning the race; success runs code on that server.
The record
- CVE
- CVE-2023-21546
- Published
- Jan 10, 2023
- Updated
- Jan 1, 2025
- Vendor
- Microsoft
- Product
- Windows 10 Version 1507
- Classifications
- CWE-416, T1190
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jan 10, 2023CVE publishedPublication date reported by the CVE source.
- Jan 1, 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 <10.0.10240.19685
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.
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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