{"cve":"CVE-2026-41181","nvd":{"published":"2026-05-15T17:16:46.320","modified":"2026-06-17T10:46:17.300","status":"Analyzed","description":"Traefik is an HTTP reverse proxy and load balancer. Prior to 2.11.44, 3.6.15, and 3.7.0-rc.3, there is an information disclosure vulnerability in Traefik's errors (custom error pages) middleware. When the backend returns a response matching the configured status range, the middleware forwards the original request's complete header set, including Authorization, Cookie, and other authentication material, to the separate error page service rather than only the minimal context needed to render the error page. This behavior is undocumented: the documentation states only that Host is forwarded by default, so operators are not warned that sensitive credentials are shared across service boundaries. Deployments using the errors middleware with a distinct error page service may inadvertently expose end-user credentials to infrastructure that was not intended to receive them. This vulnerability is fixed in 2.11.44, 3.6.15, and 3.7.0-rc.3.","cvss_v4":{"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:L/SI:N/SA:N","score":6.9},"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N","score":5.8},"cwes":["CWE-201"],"references":["https://github.com/traefik/traefik/releases/tag/v2.11.44","https://github.com/traefik/traefik/releases/tag/v3.6.15","https://github.com/traefik/traefik/releases/tag/v3.7.0-rc.3","https://github.com/traefik/traefik/security/advisories/GHSA-p6hg-qh38-555r"],"products":["traefik:traefik"],"source":"nvd","synced_at":"2026-10-19T22:35:16.954578616+00:00"},"epss":{"cve":"CVE-2026-41181","score":0.00445,"percentile":0.38763,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-p6hg-qh38-555r","url":"https://osv.dev/vulnerability/GHSA-p6hg-qh38-555r","summary":"Traefik's errors middleware forwards Authorization and Cookie headers to separate error page service","modified":"2026-08-11T20:51:09.013269938Z","packages":[{"ecosystem":"Go","name":"github.com/traefik/traefik/v2","purl":"pkg:golang/github.com/traefik/traefik/v2","ranges":["<2.11.44"],"fixed":["2.11.44"]},{"ecosystem":"Go","name":"github.com/traefik/traefik/v3","purl":"pkg:golang/github.com/traefik/traefik/v3","ranges":["<3.6.15"],"fixed":["3.6.15"]},{"ecosystem":"Go","name":"github.com/traefik/traefik/v3","purl":"pkg:golang/github.com/traefik/traefik/v3","ranges":[">=3.7.0-rc.0 <3.7.0-rc.3"],"fixed":["3.7.0-rc.3"]}]},{"id":"GO-2026-5532","url":"https://osv.dev/vulnerability/GO-2026-5532","summary":"Authorization and Cookie headers forwarded to error page service in github.com/traefik/traefik","modified":"2026-08-11T20:45:07.997227246Z","packages":[{"ecosystem":"Go","name":"github.com/traefik/traefik","purl":"pkg:golang/github.com/traefik/traefik","ranges":["all versions"],"fixed":[]},{"ecosystem":"Go","name":"github.com/traefik/traefik/v2","purl":"pkg:golang/github.com/traefik/traefik/v2","ranges":["<2.11.44"],"fixed":["2.11.44"]},{"ecosystem":"Go","name":"github.com/traefik/traefik/v3","purl":"pkg:golang/github.com/traefik/traefik/v3","ranges":["<3.6.15",">=3.7.0-rc.1 <3.7.0-rc.3"],"fixed":["3.6.15","3.7.0-rc.3"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}