AppContainer escape via exposed peer impersonation tokens
Published Oct 13, 2021 · Updated Aug 4, 2024
Privilege escalation in Microsoft Windows AppContainer allows local users to escape the sandbox through a crafted socket-security query. WSAQuerySocketSecurity returns full anonymous impersonation tokens for connected peers to AppContainer callers instead of withholding them. Exploitation requires low-privileged local code in an AppContainer, a connected peer, and user interaction; successful abuse crosses the sandbox boundary.
Summary
What happened
Privilege escalation in Microsoft Windows AppContainer allows local users to escape the sandbox through a crafted socket-security query. WSAQuerySocketSecurity returns full anonymous impersonation tokens for connected peers to AppContainer callers instead of withholding them. Exploitation requires low-privileged local code in an AppContainer, a connected peer, and user interaction; successful abuse crosses the sandbox boundary.
The record
- CVE
- CVE-2021-40476
- Published
- Oct 13, 2021
- Updated
- Aug 4, 2024
- Vendor
- Microsoft
- Product
- Windows 10 Version 1507
- Classifications
- CWE-522, T1068
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Oct 13, 2021CVE publishedPublication date reported by the CVE source.
- Aug 4, 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 <10.0.10240.19086
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
- Microsoft Windows WSAQuerySocketSecurity AppContainer Privilege Escalationproof of concept · demonstrated
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
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Your stack
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