{"action":"Upgrade matrix-synapse to 0.31.1 or later.","affected":[{"fixed":"0.31.1","introduced":"0"}],"component":"matrix-synapse","cve_ids":["CVE-2018-12291"],"ecosystem":"PyPI","epss":0.01792,"exploited":false,"fixed_versions":["0.31.1"],"ghsa_id":"GHSA-v8wm-g9f2-xjv4","id":"tcs_01M5KHCRW5548FX7PEGGPCM67W","modified_at":"2026-07-06T08:00:38.802498302Z","published_at":"2026-07-02T14:13:24.881978Z","references":["https://osv.dev/vulnerability/PYSEC-2026-664","https://nvd.nist.gov/vuln/detail/CVE-2018-12291","https://github.com/matrix-org/synapse/pull/3371","https://github.com/matrix-org/synapse/commit/0834b49c6a9b6c597a154d4b2dfcf8fff90699ec","https://github.com/matrix-org/synapse","https://github.com/matrix-org/synapse/releases/tag/v0.31.1","https://pypi.org/project/matrix-synapse","https://github.com/advisories/GHSA-v8wm-g9f2-xjv4"],"severity":{"label":"high","score":7.5},"sources":[{"source":"osv","source_id":"PYSEC-2026-664","url":"https://osv.dev/vulnerability/PYSEC-2026-664"}],"summary":"Matrix Synapse Security Filtering Flaw"}