Advisories for Golang/Github.com/Oauth2-Proxy/Oauth2-Proxy package

2025

OAuth2-Proxy's `--gitlab-group` GitLab Group Authorization config flag stopped working in v7.0.0

The –gitlab-group flag for group-based authorization in the GitLab provider stopped working in the v7.0.0 release. Regardless of the flag settings, authorization wasn't restricted. Additionally, any authenticated users had whichever groups were set in –gitlab-group added to the new X-Forwarded-Groups header to the upstream application. While adding GitLab project based authorization support in #630, a bug was introduced where the user session's groups field was populated with the –gitlab-group config …

OAuth2-Proxy has authentication bypass in oauth2-proxy skip_auth_routes due to Query Parameter inclusion

This vulnerability affects oauth2-proxy deployments using the skip_auth_routes configuration option with regex patterns. The vulnerability allows attackers to bypass authentication by crafting URLs with query parameters that satisfy the configured regex patterns, potentially gaining unauthorized access to protected resources. The issue stems from skip_auth_routes matching against the full request URI (path + query parameters) instead of just the path as documented. This discrepancy enables authentication bypass attacks where attackers append …

2021

URL Redirection to Untrusted Site ('Open Redirect')

In OAuth2 Proxy from version 5.1.1 and less than version 6.0.0, users can provide a redirect address for the proxy to send the authenticated user to at the end of the authentication flow. This is expected to be the original URL that the user was trying to access. This redirect URL is checked within the proxy and validated before redirecting the user to prevent malicious actors providing redirects to potentially …

URL Redirection to Untrusted Site ('Open Redirect')

In OAuth2 Proxy before 5.1.1, there is an open redirect vulnerability. Users can provide a redirect address for the proxy to send the authenticated user to at the end of the authentication flow. This is expected to be the original URL that the user was trying to access. This redirect URL is checked within the proxy and validated before redirecting the user to prevent malicious actors providing redirects to potentially …

URL Redirection to Untrusted Site ('Open Redirect')

OAuth2 Proxy is an open-source reverse proxy and static file server that provides authentication using Providers (Google, GitHub, and others) to validate accounts by email, domain or group. In OAuth2 Proxy before version 7.0.0, for users that use the allowlist domain feature, a domain that ended in a similar way to the intended domain could have been allowed as a redirect. For example, if a allowlist domain was configured for …

URL Redirection to Untrusted Site ('Open Redirect')

OAuth2 Proxy is an open-source reverse proxy and static file server that provides authentication using Providers (Google, GitHub, and others) to validate accounts by email, domain or group. In OAuth2 Proxy before version 7.0.0, for users that use the allowlist domain feature, a domain that ended in a similar way to the intended domain could have been allowed as a redirect. For example, if a allowlist domain was configured for …