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

An authorization bypass exists in OAuth2 Proxy as part of the email_domain enforcement option. An attacker may be able to authenticate with an email claim such as attacker@evil.com@company.com and satisfy an allowed domain check for company.com, even though the claim is not a valid email address. The issue ONLY affects deployments that rely on email_domain restrictions and accept email claim values from identity providers or claim mappings that do not …

A configuration-dependent authentication bypass exists in OAuth2 Proxy. Deployments are affected when all of the following are true: OAuth2 Proxy is configured with –reverse-proxy and at least one rule is defined with –skip_auth_routes or the legacy –skip-auth-regex OAuth2 Proxy may trust a client-supplied X-Forwarded-Uri header when –reverse-proxy is enabled and –skip-auth-route or –skip-auth-regex is configured. An attacker can spoof this header so OAuth2 Proxy evaluates authentication and skip-auth rules against …

A configuration-dependent authentication bypass exists in OAuth2 Proxy. Deployments are affected when all of the following are true: Use of skip_auth_routes or the legacy skip_auth_regex * Use of patterns that can be widened by attacker-controlled suffixes, such as ^/foo/.*/bar$ causing potential exposure of /foo/secret * Protected upstream applications that interpret # as a fragment delimiter or otherwise route the request to the protected base path In deployments that rely on …

A configuration-dependent authentication bypass exists in OAuth2 Proxy. Deployments are affected when all of the following are true: Use of skip_auth_routes or the legacy skip_auth_regex * Use of patterns that can be widened by attacker-controlled suffixes, such as ^/foo/.*/bar$ causing potential exposure of /foo/secret * Protected upstream applications that interpret # as a fragment delimiter or otherwise route the request to the protected base path In deployments that rely on …

A regression introduced in v7.11.0 is preventing OAuth2 Proxy from clearing the session cookie when rendering the sign-in page. This only impacts deployments that rely on the sign-in page as part of their logout flow. In those setups, a user may be shown the sign-in page while the existing session cookie remains valid, so the browser session is not actually logged out. On shared workstations be it browsers or devices, …

A configuration-dependent authentication bypass exists in OAuth2 Proxy. Deployments are affected when all of the following are true: OAuth2 Proxy is used with an auth_request-style integration (for example, nginx auth_request) –ping-user-agent is set or –gcp-healthchecks is enabled In affected configurations, OAuth2 Proxy will treat a request with the configured health check User-Agent value as a successful health check regardless of the requested path. This allows an unauthenticated remote attacker to …

A configuration-dependent authentication bypass exists in OAuth2 Proxy. Deployments are affected when all of the following are true: OAuth2 Proxy is used with an auth_request-style integration (for example, nginx auth_request) –ping-user-agent is set or –gcp-healthchecks is enabled In affected configurations, OAuth2 Proxy will treat a request with the configured health check User-Agent value as a successful health check regardless of the requested path. This allows an unauthenticated remote attacker to …

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 filtering logic, potentially escalating privileges in the upstream app. OAuth2 Proxy authentication/authorization itself is not compromised.

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 …

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 …

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 …

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 …

OAuth2 Proxy before 5.0 has an open redirect vulnerability. Authentication tokens could be silently harvested by an attacker. This has been patched in version 5.0.

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 …

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 …