FKIE_CVE-2026-41181

Vulnerability from fkie_nvd - Published: 2026-05-15 17:16 - Updated: 2026-05-19 12:24
Severity ?
5.8 (Medium) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N
Summary
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.
References
security-advisories@github.comhttps://github.com/traefik/traefik/releases/tag/v2.11.44Product, Release Notes
security-advisories@github.comhttps://github.com/traefik/traefik/releases/tag/v3.6.15Product, Release Notes
security-advisories@github.comhttps://github.com/traefik/traefik/releases/tag/v3.7.0-rc.3Product, Release Notes
security-advisories@github.comhttps://github.com/traefik/traefik/security/advisories/GHSA-p6hg-qh38-555rExploit, Mitigation, Patch, Vendor Advisory
Impacted products
Vendor Product Version
traefik traefik *
traefik traefik *
traefik traefik 3.7.0
traefik traefik 3.7.0
traefik traefik 3.7.0
traefik traefik 3.7.0
traefik traefik 3.7.0
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  "cveTags": [],
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      "value": "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\u0027s errors (custom error pages) middleware. When the backend returns a response matching the configured status range, the middleware forwards the original request\u0027s 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."
    }
  ],
  "id": "CVE-2026-41181",
  "lastModified": "2026-05-19T12:24:19.873",
  "metrics": {
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          "exploitMaturity": "NOT_DEFINED",
          "integrityRequirement": "NOT_DEFINED",
          "modifiedAttackComplexity": "NOT_DEFINED",
          "modifiedAttackRequirements": "NOT_DEFINED",
          "modifiedAttackVector": "NOT_DEFINED",
          "modifiedPrivilegesRequired": "NOT_DEFINED",
          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
          "modifiedSubConfidentialityImpact": "NOT_DEFINED",
          "modifiedSubIntegrityImpact": "NOT_DEFINED",
          "modifiedUserInteraction": "NOT_DEFINED",
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