{"action":"Upgrade matrix-synapse to 1.120.1 or later.","affected":[{"fixed":"1.120.1","introduced":"0"}],"component":"matrix-synapse","cve_ids":["CVE-2024-53863"],"ecosystem":"PyPI","epss":0.00606,"exploited":false,"fixed_versions":["1.120.1"],"ghsa_id":"GHSA-vp6v-whfm-rv3g","id":"tcs_01M5KGTN9MWBCA9MSWRMJACR1G","modified_at":"2026-07-07T17:46:57.380988817Z","published_at":"2026-07-07T14:34:46.538614Z","references":["https://osv.dev/vulnerability/PYSEC-2026-1615","https://github.com/element-hq/synapse/security/advisories/GHSA-vp6v-whfm-rv3g","https://nvd.nist.gov/vuln/detail/CVE-2024-53863","https://github.com/element-hq/synapse","https://pypi.org/project/matrix-synapse","https://github.com/advisories/GHSA-vp6v-whfm-rv3g"],"severity":{"label":"critical","score":9.1},"sources":[{"source":"osv","source_id":"PYSEC-2026-1615","url":"https://osv.dev/vulnerability/PYSEC-2026-1615"},{"source":"nvd","source_id":"CVE-2024-53863","url":"https://nvd.nist.gov/vuln/detail/CVE-2024-53863"}],"summary":"Synapse can be forced to thumbnail unexpected file formats, invoking external, potentially untrustworthy decoders"}