Remote restricted-user sessions via sockname confusion
Published Jul 10, 2026 · Updated Jul 10, 2026
Improper authentication in RabbitMQ Server before 3.13.15, 4.0.20, 4.1.11, or 4.2.6 allows remote attackers to open loopback-restricted sessions. The affected protocol paths give the accepted socket to the loopback gate, whose is_loopback helper reads the listener-side sockname rather than the client peer address. Exploitation requires valid restricted-user credentials, a trusted PROXY-protocol frontend, and a loopback-bound listener; the demonstrated result is a live session with that user's existing permissions.
Summary
What happened
Improper authentication in RabbitMQ Server before 3.13.15, 4.0.20, 4.1.11, or 4.2.6 allows remote attackers to open loopback-restricted sessions. The affected protocol paths give the accepted socket to the loopback gate, whose is_loopback helper reads the listener-side sockname rather than the client peer address. Exploitation requires valid restricted-user credentials, a trusted PROXY-protocol frontend, and a loopback-bound listener; the demonstrated result is a live session with that user's existing permissions.
The record
- CVE
- CVE-2026-57216
- Published
- Jul 10, 2026
- Updated
- Jul 10, 2026
- Vendor
- RabbitMQ
- Product
- RabbitMQ Server
- Classifications
- CWE-287, T1078
- Attack vector
- network
- 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=>= 3.13.0, < 3.13.15
- Affected versionversion=>= 4.0.0, < 4.0.21
- Affected versionversion=>= 4.1.0, < 4.1.11
- Affected versionversion=>= 4.2.0, < 4.2.6
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
- RabbitMQ AMQP PROXY-protocol loopback bypass PoCproof 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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