EUVD-2026-41940

Traefik: Incomplete fix for CVE-2026-33433 + CVE-2026-39858 cross-cohort: headerField underscore-variant identity spoofing in BasicAuth / DigestAuth / ForwardAuth...

SUSE CVE-2026-54763

Traefik is an HTTP reverse proxy and load balancer. Prior to v2.11.51, v3.6.22, and v3.7.6, Traefik's BasicAuth, DigestAuth, and ForwardAuth middlewares strip canonical-cased spoofed identity headers before writing Traefik's own value, but do not account for underscore-variant header names, which...

Improper Handling of Case Sensitivity

Overview github.com/traefik/traefik/v2/pkg/server is a server package for traefik, a cloud native edge router. Affected versions of this package are vulnerable to Improper Handling of Case Sensitivity via the handling of HTTP headers in authentication middlewares. An attacker can impersonate user...

Improper Handling of Case Sensitivity

Overview Affected versions of this package are vulnerable to Improper Handling of Case Sensitivity via the handling of HTTP headers in authentication middlewares. An attacker can impersonate users or escalate privileges by injecting underscore-variant headers that bypass canonical header strippin...

Improper Handling of Case Sensitivity

Overview Affected versions of this package are vulnerable to Improper Handling of Case Sensitivity via the handling of HTTP headers in authentication middlewares. An attacker can impersonate users or escalate privileges by injecting underscore-variant headers that bypass canonical header strippin...

Improper Handling of Case Sensitivity

Overview Affected versions of this package are vulnerable to Improper Handling of Case Sensitivity via the handling of HTTP headers in authentication middlewares. An attacker can impersonate users or escalate privileges by injecting underscore-variant headers that bypass canonical header strippin...

CVE-2026-54763

Traefik is an HTTP reverse proxy and load balancer. Prior to v2.11.51, v3.6.22, and v3.7.6, Traefik's BasicAuth, DigestAuth, and ForwardAuth middlewares strip canonical-cased spoofed identity headers before writing Traefik's own value, but do not account for underscore-variant header names, which...

CVE-2026-54763 Traefik: headerField underscore-variant identity spoofing in BasicAuth / DigestAuth / ForwardAuth

Traefik is an HTTP reverse proxy and load balancer. Prior to v2.11.51, v3.6.22, and v3.7.6, Traefik's BasicAuth, DigestAuth, and ForwardAuth middlewares strip canonical-cased spoofed identity headers before writing Traefik's own value, but do not account for underscore-variant header names, which...

CVE-2026-54763 Traefik: headerField underscore-variant identity spoofing in BasicAuth / DigestAuth / ForwardAuth

Traefik is an HTTP reverse proxy and load balancer. Prior to v2.11.51, v3.6.22, and v3.7.6, Traefik's BasicAuth, DigestAuth, and ForwardAuth middlewares strip canonical-cased spoofed identity headers before writing Traefik's own value, but do not account for underscore-variant header names, which...

CVE-2026-54763

Traefik is an HTTP reverse proxy and load balancer. Prior to v2.11.51, v3.6.22, and v3.7.6, Traefik's BasicAuth, DigestAuth, and ForwardAuth middlewares strip canonical-cased spoofed identity headers before writing Traefik's own value, but do not account for underscore-variant header names, which...

CVE-2026-54763

Traefik is an HTTP reverse proxy and load balancer. Prior to v2.11.51, v3.6.22, and v3.7.6, Traefik's BasicAuth, DigestAuth, and ForwardAuth middlewares strip canonical-cased spoofed identity headers before writing Traefik's own value, but do not account for underscore-variant header names, which...

PT-2026-56011

Name of the Vulnerable Software and Affected Versions Traefik versions prior to 2.11.51 Traefik versions prior to 3.6.22 Traefik versions prior to 3.7.6 Description Traefik's BasicAuth, DigestAuth, and ForwardAuth middlewares fail to account for underscore-variant header names when stripping...

SUSE CVE-2026-39858

Traefik is an HTTP reverse proxy and load balancer. Prior to versions 2.11.43, 3.6.14, and 3.7.0-rc.2, there is a high severity authentication bypass vulnerability in Traefik's ForwardAuth and snippet-based authentication middleware. Traefik's forwarded-header sanitization logic targets only...

CVE-2026-39858 Traefik: Forwarded alias spoofing top pre-auth decision bypass

Traefik is an HTTP reverse proxy and load balancer. Prior to versions 2.11.43, 3.6.14, and 3.7.0-rc.2, there is a high severity authentication bypass vulnerability in Traefik's ForwardAuth and snippet-based authentication middleware. Traefik's forwarded-header sanitization logic targets only...

CVE-2026-39858

Traefik is an HTTP reverse proxy and load balancer. Prior to versions 2.11.43, 3.6.14, and 3.7.0-rc.2, there is a high severity authentication bypass vulnerability in Traefik's ForwardAuth and snippet-based authentication middleware. Traefik's forwarded-header sanitization logic targets only...

OAuth2-Proxy is vulnerable to header smuggling via underscore leading to potential privilege escalation

Impact All deployments of OAuth2 Proxy in front of applications that normalize underscores to dashes in HTTP headers e.g., WSGI-based frameworks such as Django, Flask, FastAPI, and PHP applications. Authenticated users can inject underscore variants of X-Forwarded- headers that bypass the proxy’s...

GHSA-VJRC-MH2V-45X6 OAuth2-Proxy is vulnerable to header smuggling via underscore leading to potential privilege escalation

Impact All deployments of OAuth2 Proxy in front of applications that normalize underscores to dashes in HTTP headers e.g., WSGI-based frameworks such as Django, Flask, FastAPI, and PHP applications. Authenticated users can inject underscore variants of X-Forwarded- headers that bypass the proxy’s...

EUVD-2025-50825

OAuth2-Proxy is vulnerable to header smuggling via underscore leading to potential privilege escalation...

CVE-2025-64484

A header-smuggling vulnerability was found in OAuth2-Proxy’s handling of HTTP headers containing underscores such as XForwardedFor. The proxy failed to properly normalize these header names, which could allow crafted requests to bypass header validation or filtering. When OAuth2-Proxy is deployed...

BIT-OAUTH2-PROXY-2025-64484 OAuth2-Proxy vulnerable to header smuggling via underscore, leading to potential privilege escalation

OAuth2-Proxy is an open-source tool that can act as either a standalone reverse proxy or a middleware component integrated into existing reverse proxy or load balancer setups. In versions prior to 7.13.0, all deployments of OAuth2 Proxy in front of applications that normalize underscores to dashe...