{"id":"CVE-2020-5207","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.","aliases":["GHSA-xrr9-rh8p-433v"],"modified":"2026-07-09T01:25:35.403595Z","published":"2020-01-27T20:15:10.980Z","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"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/ktorio/ktor","events":[{"introduced":"0"},{"fixed":"2dfa1798f0b026d781efd5e0bc4e6d9a5cfcec3e"}],"database_specific":{"cpe":"cpe:2.3:a:jetbrains:ktor:*:*:*:*:*:*:*:*","extracted_events":[{"introduced":"0"},{"fixed":"1.3.0"}],"source":"CPE_RANGE"}}],"versions":["1.3.0-rc2","1.3.0-rc","1.3.0-beta-2","1.3.0-beta-1","1.2.3","1.2.3-rc","1.2.2","1.2.1","1.2.0","1.2.0-rc2","1.2.0-rc","1.2.0-alpha-2","1.2.0-alpha-1","1.1.2","1.1.1","1.1.0","1.0.1","1.0.0","1.0.0-rc","1.0.0-beta-4","1.0.0-beta-3","1.0.0-beta-2","1.0.0-beta-1","1.0.0-alpha-3","1.0.0-alpha-2","1.0.0-alpha-1","0.9.5","0.9.4","0.9.4-dev-3","0.9.4-alpha-2","0.9.3-alpha-4","0.9.3-alpha-3","0.9.3-alpha-2","0.9.3-alpha-1","0.9.2","0.9.2-alpha-6","0.9.2-alpha-5","0.9.2-alpha-4","0.9.2-alpha-3","0.9.2-alpha-2","0.9.2-alpha-1","0.9.1","0.9.1-alpha-10","0.9.1-alpha-9","0.9.1-alpha-8","0.9.1-alpha-7","0.9.1-alpha-6","0.9.1-alpha-5","0.9.1-alpha-4","0.9.0","0.9.0-alpha-3","0.9.0-alpha-2","build-0.4.1-alpha-16","ktor-0.4.0","build-0.4.0-alpha-15","build-0.4.0-alpha-14","build-0.4.0-alpha-13","build-0.4.0-alpha-12","build-0.4.0-alpha-11","build-0.4.0-alpha-10","build-0.4.0-alpha-9","build-0.4.0-alpha-8","build-0.4.0-alpha-7","build-0.4.0-alpha-6","ktor-0.3.3","ktor-0.3.2","ktor-0.3.1","ktor-0.3.0","ktor-0.2.4","ktor-0.2.3","ktor-0.2.2","ktor-0.2.1","ktor-0.2.0","ktor-0.1.8","ktor-0.1.7","ktor-0.1.6","ktor-0.1.5","ktor-0.1.4","ktor-0.1.3","ktor-0.1.2"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2020-5207.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N"}]}