{"id":"CVE-2022-31152","url":"https://www.cyber-defence.io/tools/cve/CVE-2022-31152","generatedAt":"2026-10-27T19:05:09.142Z","title":"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.","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.","published":"2022-09-02T20:15:08.000Z","lastModified":"2026-06-17T04:44:55.000Z","status":"Modified","sourceIdentifier":"security-advisories@github.com","cvss":{"version":"3.1","score":7.5,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},"cwe":["CWE-703","CWE-755"],"affected":["matrix/synapse"],"epss":{"score":0.01177,"percentile":0.67419,"date":"2026-10-26","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"high","text":"High impact if exploited, but EPSS currently rates exploitation as unlikely (1.18%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"https://github.com/matrix-org/synapse/pull/13087","tags":["Issue Tracking","Patch","Third Party Advisory"],"source":"security-advisories@github.com"},{"url":"https://github.com/matrix-org/synapse/pull/13088","tags":["Issue Tracking","Patch","Third Party Advisory"],"source":"security-advisories@github.com"},{"url":"https://github.com/matrix-org/synapse/releases/tag/v1.62.0","tags":["Release Notes","Third Party Advisory"],"source":"security-advisories@github.com"},{"url":"https://github.com/matrix-org/synapse/security/advisories/GHSA-jhjh-776m-4765","tags":["Issue Tracking","Mitigation","Third Party Advisory"],"source":"security-advisories@github.com"},{"url":"https://github.com/matrix-org/synapse/pull/13087","tags":["Issue Tracking","Patch","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://github.com/matrix-org/synapse/pull/13088","tags":["Issue Tracking","Patch","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://github.com/matrix-org/synapse/releases/tag/v1.62.0","tags":["Release Notes","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://github.com/matrix-org/synapse/security/advisories/GHSA-jhjh-776m-4765","tags":["Issue Tracking","Mitigation","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2022-31152","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}