{"action":"Upgrade matrix-synapse to 0.34.0.1 or later.","affected":[{"fixed":"0.34.0.1","introduced":"0"}],"component":"matrix-synapse","cve_ids":["CVE-2019-5885"],"ecosystem":"PyPI","epss":0.02485,"exploited":false,"fixed_versions":["0.34.0.1"],"ghsa_id":"GHSA-jrqm-v8cv-53ww","id":"tcs_01M5KG8VE0Y0RSQMZ6Z2XBK27H","modified_at":"2026-06-10T17:00:58.147133053Z","published_at":"2019-03-21T16:01:00Z","references":["https://osv.dev/vulnerability/PYSEC-2019-187","https://matrix.org/blog/2019/01/15/further-details-on-critical-security-update-in-synapse-affecting-all-versions-prior-to-0-34-1-cve-2019-5885/","https://matrix.org/blog/2019/01/10/critical-security-update-synapse-0-34-0-1-synapse-0-34-1-1/","https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/VMCLO5PUPBA756UKY72PKUWL4RRM4W6K/","https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/32Y6KD3OAHCG5P33HC2QEX3NUZOSXCGZ/","https://github.com/advisories/GHSA-jrqm-v8cv-53ww"],"severity":{"label":"high","score":7.5},"sources":[{"source":"osv","source_id":"PYSEC-2019-187","url":"https://osv.dev/vulnerability/PYSEC-2019-187"},{"source":"nvd","source_id":"CVE-2019-5885","url":"https://nvd.nist.gov/vuln/detail/CVE-2019-5885"}],"summary":"Matrix Synapse before 0.34.0.1, when the macaroon_secret_key authentication parameter is not set, uses a predictable value to derive a secret key and other secrets which could allow remote attackers t"}