{"cve":"CVE-2022-39374","nvd":{"published":"2023-05-26T14:15:10.257","modified":"2026-06-17T04:58:14.383","status":"Modified","description":"Synapse is an open-source Matrix homeserver written and maintained by the Matrix.org Foundation. If Synapse and a malicious homeserver are both joined to the same room, the malicious homeserver can trick Synapse into accepting previously rejected events into its view of the current state of that room. This can be exploited in a way that causes all further messages and state changes sent in that room from the vulnerable homeserver to be rejected. This issue has been patched in version 1.68.0","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":6.5},"cwes":["CWE-400"],"references":["https://github.com/matrix-org/synapse/pull/13723","https://github.com/matrix-org/synapse/security/advisories/GHSA-p9qp-c452-f9r7","https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/UJIJRP5ZH6B3KGFLHCAKR2IX2Y4Z25QD/","https://github.com/matrix-org/synapse/pull/13723","https://github.com/matrix-org/synapse/security/advisories/GHSA-p9qp-c452-f9r7"],"products":["matrix:synapse"],"source":"nvd","synced_at":"2026-10-19T21:38:24.161619714+00:00"},"epss":{"cve":"CVE-2022-39374","score":0.00941,"percentile":0.60987,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-p9qp-c452-f9r7","url":"https://osv.dev/vulnerability/GHSA-p9qp-c452-f9r7","summary":"Synapse Denial of service due to incorrect application of event authorization rules during state resolution","modified":"2024-09-30T20:38:17.872853Z","packages":[{"ecosystem":"PyPI","name":"matrix-synapse","purl":"pkg:pypi/matrix-synapse","ranges":[">=1.62.0 <1.68.0rc1"],"fixed":["1.68.0rc1"]}]},{"id":"PYSEC-2023-66","url":"https://osv.dev/vulnerability/PYSEC-2023-66","summary":"","modified":"2023-11-08T04:10:20.163376Z","packages":[{"ecosystem":"PyPI","name":"matrix-synapse","purl":"pkg:pypi/matrix-synapse","ranges":[">=1.62.0 <1.68.0"],"fixed":["1.68.0"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}