{"id":"CVE-2024-1135","aliases":["GHSA-w3h3-4rj7-4ph4","PYSEC-2026-1434"],"url":"https://o3.security/vulnerability/CVE-2024-1135","summary":"Request smuggling leading to endpoint restriction bypass in Gunicorn","details":"Gunicorn fails to properly validate Transfer-Encoding headers, leading to HTTP Request Smuggling (HRS) vulnerabilities. By crafting requests with conflicting Transfer-Encoding headers, attackers can bypass security restrictions and access restricted endpoints. This issue is due to Gunicorn's handling of Transfer-Encoding headers, where it incorrectly processes requests with multiple, conflicting Transfer-Encoding headers, treating them as chunked regardless of the final encoding specified. This vulnerability allows for a range of attacks including cache poisoning, session manipulation, and data exposure.","published":"2024-04-16T00:15:07Z","modified":"2026-07-07T17:56:46.941801320Z","cvss":{"score":8.2,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:N"},"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"PyPI","name":"gunicorn","fixedVersion":"22.0.0"}],"fix":null,"references":[{"type":"WEB","url":"https://huntr.com/bounties/22158e34-cfd5-41ad-97e0-a780773d96c1"},{"type":"WEB","url":"https://lists.debian.org/debian-lts-announce/2024/06/msg00027.html"},{"type":"WEB","url":"https://lists.debian.org/debian-lts-announce/2024/12/msg00018.html"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-07-07T17:56:46.941801320Z"}}