Freeze the Controller, Defrost the Food: Uncovering Vulnerabilities in Danfoss Refrigeration Controllers

Team82/Claroty analyzed the Danfoss AK-SM 800A refrigeration management platform and identified multiple high-impact vulnerabilities — a reproducible hidden "code-of-the-day" authentication bypass, an unauthenticated-to-authenticated path enabling authenticated command injection and remote code execution via email settings, and the ability to upload/modify the externally exposed Nginx headers.conf leading to traffic manipulation or denial-of-service; thousands of devices were internet-accessible and Danfoss released firmware R4.3.1 to address the issues.