{"action":"Upgrade synapse to 1.20.0-r0 or later.","affected":[{"fixed":"1.20.0-r0","introduced":"0"}],"component":"synapse","cve_ids":[],"ecosystem":"Alpine","ecosystem_qualifier":"Alpine:v3.19","exploited":false,"fixed_versions":["1.20.0-r0"],"id":"tcs_01M6GM5DH44XTSG34GKBAD7HPF","modified_at":"2026-11-03T06:32:25.017715232Z","published_at":"2020-11-24T03:15:13.120Z","references":["https://osv.dev/vulnerability/ALPINE-CVE-2020-26890","https://security.alpinelinux.org/vuln/CVE-2020-26890"],"severity":{"label":"high","score":7.5},"sources":[{"source":"osv","source_id":"ALPINE-CVE-2020-26890#Alpine:v3.19/synapse","url":"https://osv.dev/vulnerability/ALPINE-CVE-2020-26890"}],"summary":"Matrix Synapse before 1.20.0 erroneously permits non-standard NaN, Infinity, and -Infinity JSON values in fields of m.room.member events, allowing remote attackers to execute a denial of service attac"}