GO-2026-5559 OAuth2 Proxy has an Authentication Bypass via Fragment Confusion in skip_auth_routes and skip_auth_regex in github.com/oauth2-proxy/oauth2-proxy

OAuth2 Proxy has an Authentication Bypass via Fragment Confusion in skipauthroutes and skipauthregex in github.com/oauth2-proxy/oauth2-proxy...

User Impersonation

Overview Affected versions of this package are vulnerable to User Impersonation via the X-Forwarded-Uri header when the --reverse-proxy setting is enabled and either --skip-auth-regex or --skip-auth-route is configured. An attacker can gain unauthorized access to protected routes by spoofing the...

CVE-2026-40575 OAuth2 Proxy has an Authentication Bypass via X-Forwarded-Uri Header Spoofing

OAuth2 Proxy is a reverse proxy that provides authentication using OAuth2 providers. Versions 7.5.0 through 7.15.1 may trust a client-supplied X-Forwarded-Uri header when --reverse-proxy is enabled and --skip-auth-regex or --skip-auth-route is configured. An attacker can spoof this header so OAut...

CVE-2026-41059 OAuth2 Proxy has an Authentication Bypass via Fragment Confusion in skip_auth_routes and skip_auth_regex

OAuth2 Proxy is a reverse proxy that provides authentication using OAuth2 providers. Versions 7.5.0 through 7.15.1 have a configuration-dependent authentication bypass. Deployments are affected when all of the following are true: Use of skipauthroutes or the legacy skipauthregex; use of patterns...