{"id":"CVE-2020-5207","aliases":["GHSA-xrr9-rh8p-433v"],"url":"https://o3.security/vulnerability/CVE-2020-5207","summary":"Request smuggling is possible when both chunked TE and content length specified","details":"In Ktor before 1.3.0, request smuggling is possible when running behind a proxy that doesn't handle Content-Length and Transfer-Encoding properly or doesn't handle \\n as a headers separator.","published":"2020-01-27T20:15:10.980Z","modified":"2026-07-09T01:25:35.403595Z","cvss":{"score":7.5,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N"},"epss":null,"cisaKev":null,"exploitsKnown":null,"affectedPackages":[{"ecosystem":"Maven","name":"io.ktor:ktor-client-cio","fixedVersion":"1.3.0"},{"ecosystem":"Maven","name":"io.ktor:ktor-server-cio","fixedVersion":"1.3.0"}],"fix":{"url":"https://github.com/ktorio/ktor/pull/1547","label":"ktorio/ktor#1547"},"references":[{"type":"ADVISORY","url":"https://github.com/ktorio/ktor/security/advisories/GHSA-xrr9-rh8p-433v"},{"type":"FIX","url":"https://github.com/ktorio/ktor/pull/1547"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-07-09T01:25:35.403595Z"}}