Invoice Ninja 5.13.26 - Open Redirect in Client Portal Login via intended Parameter

Invoice Ninja through 5.13.26 contains an open redirect vulnerability in the client portal login that allows unauthenticated attackers to redirect authenticated victims to attacker-controlled external URLs by injecting a malicious value into the intended query parameter. Attackers can craft a client login link with an external URL in the intended parameter, which is stored in the session without host validation and emitted verbatim via a bare redirect in the ContactLoginController authenticated() handler after the victim completes a legitimate login, enabling phishing attacks.