CVEvulnerability

CVE-2026-41181

6.9 MEDIUM Published 2026-05-15 Modified 2026-06-17 Official page ↗
Status
Analyzed
Published
2026-05-15
Last modified
2026-06-17
Assigner
[email protected]
CVSS 4.0 ([email protected])
6.9 MEDIUM — 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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CVSS 3.1 ([email protected])
5.8 MEDIUM — CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N
Weaknesses
CWE-201

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.

Affected configurations

• traefik traefik (< 2.11.44) • traefik traefik (>= 3.0.0 < 3.6.15) • traefik traefik 3.7.0

Related

Weakness · CWE (1)

  • CWE-201 Insertion of Sensitive Information Into Sent Data weakness

References