{"id":"CVE-2026-29054","summary":"Traefik: lowercase `Connection` tokens can delete traefik-managed forwarded identity headers (for example, `X-Real-Ip`)","details":"Traefik is an HTTP reverse proxy and load balancer. From version 2.11.9 to 2.11.37 and from version 3.1.3 to 3.6.8, there is a potential vulnerability in Traefik managing the Connection header with X-Forwarded headers. When Traefik processes HTTP/1.1 requests, the protection put in place to prevent the removal of Traefik-managed X-Forwarded headers (such as X-Real-Ip, X-Forwarded-Host, X-Forwarded-Port, etc.) via the Connection header does not handle case sensitivity correctly. The Connection tokens are compared case-sensitively against the protected header names, but the actual header deletion operates case-insensitively. As a result, a remote unauthenticated client can use lowercase Connection tokens (e.g. Connection: x-real-ip) to bypass the protection and trigger the removal of Traefik-managed forwarded identity headers. This issue has been patched in versions 2.11.38 and 3.6.9.","aliases":["GHSA-92mv-8f8w-wq52","GO-2026-4597"],"modified":"2026-04-16T02:14:27.857949036Z","published":"2026-03-05T16:18:49.230Z","related":["SUSE-SU-2026:1042-1","openSUSE-SU-2026:10314-1","openSUSE-SU-2026:10323-1"],"database_specific":{"cna_assigner":"GitHub_M","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/29xxx/CVE-2026-29054.json","cwe_ids":["CWE-178"]},"references":[{"type":"WEB","url":"https://github.com/traefik/traefik/releases/tag/v2.11.38"},{"type":"WEB","url":"https://github.com/traefik/traefik/releases/tag/v3.6.9"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/29xxx/CVE-2026-29054.json"},{"type":"ADVISORY","url":"https://github.com/traefik/traefik/security/advisories/GHSA-92mv-8f8w-wq52"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-29054"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/traefik/traefik","events":[{"introduced":"06d7fab820dc1e486fe59371aeb359c965767ded"},{"fixed":"7c55452b21e7465d95bd731725c7222f7626265b"}],"database_specific":{"versions":[{"introduced":"2.11.9"},{"fixed":"2.11.38"}]}},{"type":"GIT","repo":"https://github.com/traefik/traefik","events":[{"introduced":"89f3b272c3d4ed3f075f92f8acca494cdba4f708"},{"fixed":"65f9d0663202b0ebf7941da0c4af0f1953525ce6"}],"database_specific":{"versions":[{"introduced":"3.1.3"},{"fixed":"3.6.9"}]}}],"versions":["v2.11.10","v2.11.11","v2.11.12","v2.11.13","v2.11.14","v2.11.15","v2.11.16","v2.11.17","v2.11.18","v2.11.19","v2.11.20","v2.11.21","v2.11.22","v2.11.23","v2.11.24","v2.11.25","v2.11.26","v2.11.27","v2.11.28","v2.11.29","v2.11.30","v2.11.31","v2.11.32","v2.11.33","v2.11.34","v2.11.35","v2.11.36","v2.11.37","v2.11.9"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-29054.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"}]}