CVE-2026-36537 [CRITICAL] – ThingsBoard v4.3.0.1 is vulnerable to an authentication bypass during the OAuth authorizat

ThingsBoard v4.3.0.1 is vulnerable to an authentication bypass during the OAuth authorization code exchange. The application improperly trusts user-supplied identity data within the user parameter of the /login/oauth2/code/ endpoint. By manipulating the email address in this JSON object, a remote attacker can bypass authentication and gain full access to any existing user account on the platform without possessing the target user’s credentials. This results in a complete account takeover.