OAuth2 Proxy is a reverse proxy that provides authentication using OAuth2 providers. A regression introduced in 7.11.0 prevents OAuth2 Proxy from clearing the session cookie when rendering the sign-in page. In deployments that rely on the sign-in page as part of their logout flow, a user may be shown the sign-in page while the existing session cookie remains valid, meaning the browser session is not actually logged out. On shared workstations or devices, a subsequent user could continue to use the previous user's authenticated session. Deployments that use a dedicated logout/sign-out endpoint to terminate sessions are not affected. This issue is fixed in 7.15.2

Affected: Go: github.com/oauth2-proxy/oauth2-proxy/v7

### Impact A regression introduced in [v7.11.0](https://github.com/oauth2-proxy/oauth2-proxy/pull/2605) 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 subsequent user could continue to use the previous user's authenticated session.

Deployments that use a dedicated logout/sign-out endpoint to terminate sessions are not affected.

### Patches This issue is fixed in v7.15.2.

### Workarounds Do not rely on the sign-in page to clear an existing session. Instead:

- Use the dedicated logout/sign-out endpoint of OAuth2 Proxy - Ensure your application logout flow explicitly clears the OAuth2 Proxy session cookie before redirecting users to the sign-in page - If needed, clear the session cookie at the reverse proxy or application layer as a temporary mitigation