Traccar Vulnerable to Authorization Code Theft via Open Redirect in OIDC Provider Endpoints

Versions of the Traccar open-source GPS tracking system up to and including 6.11.1 contain an issue in which authenticated users can steal OAuth 2.0 authorization codes by exploiting an open redirect vulnerability in two OIDC-related endpoints. The `redirect_uri` parameter is not validated against a whitelist, allowing attackers to redirect authorization codes to attacker-controlled URLs, enabling account takeover on any OAuth-integrated application. As of time of publication, it is unclear whether a fix is available.