CVE-2022-31152: matrix-org synapse

Vulnerability summary

CVE-2022-31152 is a high (CVSS 7.5) vulnerability in matrix-org synapse. EPSS estimates a 1.18% chance of exploitation in the next 30 days, higher than 67.1% of scored vulnerabilities.

Timeline

1. 02-09-2022
   PublishedVulnerability first disclosed.
2. 23-04-2025
   Last modifiedVulnerability information updated.

Description

Synapse is an open-source Matrix homeserver written and maintained by the Matrix.org Foundation. The Matrix specification specifies a list of [event authorization rules](https://spec.matrix.org/v1.2/rooms/v9/#authorization-rules) which must be checked when determining if an event should be accepted into a room. In versions of Synapse up to and including version 1.61.0, some of these rules are not correctly applied. An attacker could craft events which would be accepted by Synapse but not a spec-conformant server, potentially causing divergence in the room state between servers. Administrators of homeservers with federation enabled are advised to upgrade to version 1.62.0 or higher. Federation can be disabled by setting [`federation_domain_whitelist`](https://matrix-org.github.io/synapse/latest/usage/configuration/config_documentation.html#federation_domain_whitelist) to an empty list (`[]`) as a workaround.

• CWE-703Improper Check or Handling of Exceptional ConditionsThe product does not properly anticipate or handle exceptional conditions that rarely occur during normal operation of the product.
• CWE-755Improper Handling of Exceptional ConditionsThe product does not handle or incorrectly handles an exceptional condition.