SSRF in Sydent due to missing validation of hostnames
Vulnerability Description
Sydent is a reference Matrix identity server. Sydent can be induced to send HTTP GET requests to internal systems, due to lack of parameter validation or IP address blacklisting. It is not possible to exfiltrate data or control request headers, but it might be possible to use the attack to perform an internal port enumeration. This issue has been addressed in in 9e57334, 8936925, 3d531ed, 0f00412. A potential workaround would be to use a firewall to ensure that Sydent cannot reach internal HTTP resources.
Impact Analysis
Refer to official advisory for detailed impact metrics.
Remediation
Ensure systems are updated to the latest vendor-supplied patch levels.
Am I Vulnerable?
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Credits & Attribution
No credits recorded in the NVD database.
References
- https://pypi.org/project/matrix-sydent/
- https://github.com/matrix-org/sydent/releases/tag/v2.3.0
- https://github.com/matrix-org/sydent/security/advisories/GHSA-9jhm-8m8c-c3f4
- https://github.com/matrix-org/sydent/commit/9e573348d81df8191bbe8c266c01999c9d57cd5f
- https://github.com/matrix-org/sydent/commit/8936925f561b0c352c2fa922d5097d7245aad00a
- https://github.com/matrix-org/sydent/commit/3d531ed50d2fd41ac387f36d44d3fb2c62dd22d3
- https://github.com/matrix-org/sydent/commit/0f00412017f25619bc36c264b29ea96808bf310a
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