{"action":"Upgrade puma to 3.12.4 or later.","affected":[{"fixed":"3.12.4","introduced":"0"},{"fixed":"4.3.3","introduced":"4.0.0"}],"component":"puma","cve_ids":["CVE-2020-5247"],"ecosystem":"RubyGems","epss":0.02549,"exploited":false,"fixed_versions":["3.12.4","4.3.3"],"ghsa_id":"GHSA-84j7-475p-hp8v","id":"tcs_01M5KEHVTETX4HR7F6AS1KJBDX","modified_at":"2026-07-08T06:27:02.150553465Z","published_at":"2020-02-28T16:53:55Z","references":["https://osv.dev/vulnerability/GHSA-84j7-475p-hp8v","https://github.com/puma/puma/security/advisories/GHSA-84j7-475p-hp8v","https://nvd.nist.gov/vuln/detail/CVE-2020-5247","https://github.com/puma/puma/commit/c36491756f68a9d6a8b3a49e7e5eb07fe6f1332f","https://github.com/puma/puma","https://github.com/rubysec/ruby-advisory-db/blob/master/gems/puma/CVE-2020-5247.yml","https://lists.debian.org/debian-lts-announce/2022/05/msg00034.html","https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/BMJ3CGZ3DLBJ5WUUKMI5ZFXFJQMXJZIK","https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/DIHVO3CQMU7BZC7FCTSRJ33YDNS3GFPK","https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/NJ3LL5F5QADB6LM46GXZETREAKZMQNRD","https://owasp.org/www-community/attacks/HTTP_Response_Splitting","https://www.ruby-lang.org/en/news/2019/10/01/http-response-splitting-in-webrick-cve-2019-16254"],"severity":{"label":"medium","score":6.5},"sources":[{"source":"osv","source_id":"GHSA-84j7-475p-hp8v","url":"https://osv.dev/vulnerability/GHSA-84j7-475p-hp8v"}],"summary":"HTTP Response Splitting in Puma"}