{"id":"GHSA-vmcc-4p4x-x7wg","summary":"Matrix Synapse DoS","details":"Matrix Synapse before 0.28.1 is prone to a denial of service flaw where malicious events injected with depth = 2\u003csup\u003e63\u003c/sup\u003e - 1 render rooms unusable, related to `federation/federation_base.py` and `handlers/message.py`, as exploited in the wild in April 2018.","aliases":["CVE-2018-10657","PYSEC-2026-846"],"modified":"2026-07-07T11:56:12.318339049Z","published":"2022-05-14T03:20:03Z","database_specific":{"nvd_published_at":"2018-05-02T16:29:00Z","cwe_ids":["CWE-20"],"severity":"HIGH","github_reviewed":true,"github_reviewed_at":"2023-07-25T19:54:26Z"},"references":[{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2018-10657"},{"type":"WEB","url":"https://github.com/matrix-org/synapse/commit/33f469ba19586bbafa0cf2c7d7c35463bdab87eb"},{"type":"WEB","url":"https://docs.google.com/document/d/1I3fi2S-XnpO45qrpCsowZv8P8dHcNZ4fsBsbOW7KABI/edit#heading=h.fj95ykuss7s1"},{"type":"PACKAGE","url":"https://github.com/matrix-org/synapse"},{"type":"WEB","url":"https://matrix.org/blog/2018/05/01/security-update-synapse-0-28-1"}],"affected":[{"package":{"name":"matrix-synapse","ecosystem":"PyPI","purl":"pkg:pypi/matrix-synapse"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.28.1"}]}],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2022/05/GHSA-vmcc-4p4x-x7wg/GHSA-vmcc-4p4x-x7wg.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"}]}