{"id":"CVE-2026-88007","summary":"Traefik HTTP/3 Backend NTLM Connection Reuse","details":"Traefik is an open source HTTP reverse proxy and load balancer. From 2.11.0 until 2.11.57 and 3.7.13, the HTTP/3 entrypoint ConnContext does not call service.AddTransportOnContext, so kerberosRoundTripper uses a shared backend transport instead of a transport dedicated to each frontend connection. With HTTP/3 enabled, a backend using connection-bound NTLM or Negotiate authentication, and backend keep-alive, an unrelated client can reuse a backend connection authenticated for a victim, read victim-only data, and act as that victim without the victim credentials. This issue is fixed in 2.11.57 and 3.7.13.","aliases":["GHSA-qqjf-53cj-pwvv","GO-2026-6466"],"modified":"2026-09-27T18:26:37.752119879Z","published":"2026-09-10T14:47:28.270Z","related":["SUSE-SU-2026:23855-1","SUSE-SU-2026:23863-1","openSUSE-SU-2026:21897-1"],"database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/88xxx/CVE-2026-88007.json","cna_assigner":"GitHub_M","cwe_ids":["CWE-287","CWE-863"]},"references":[{"type":"WEB","url":"https://github.com/traefik/traefik/releases/tag/v2.11.57"},{"type":"WEB","url":"https://github.com/traefik/traefik/releases/tag/v3.7.13"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/88xxx/CVE-2026-88007.json"},{"type":"ADVISORY","url":"https://github.com/traefik/traefik/security/advisories/GHSA-qqjf-53cj-pwvv"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-88007"},{"type":"FIX","url":"https://github.com/traefik/traefik/commit/ff39c47d7459dec9cd8de63c1a4e7aa7315bdc1c"},{"type":"FIX","url":"https://github.com/traefik/traefik/pull/13812"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/traefik/traefik","events":[{"introduced":"23c26d64eeb72eaecaecedc31ca740e83304fde2"},{"fixed":"d87731461f0c7beb6fdbcc5a5655a44ce56e537a"},{"introduced":"d99d2f95e66a28ee8180634dc80fdf13ba68c62a"},{"fixed":"e8f398ee30ca5643158ea9094b701b8eae9849e5"},{"fixed":"ff39c47d7459dec9cd8de63c1a4e7aa7315bdc1c"},{"fixed":"839eb7f48a16849f22762b7e3bdfc58253146cd7"},{"fixed":"fc92cc118a0557a029c7019d5ee06665127b0f13"}],"database_specific":{"extracted_events":[{"introduced":"2.8.2"},{"fixed":"2.11.56"},{"introduced":"3.0.0"},{"fixed":"3.7.12"}],"source":["CPE_RANGE","REFERENCES"],"cpe":"cpe:2.3:a:traefik:traefik:*:*:*:*:*:*:*:*"}}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-88007.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N"}]}