Freeze the Controller, Defrost the Food: Uncovering Vulnerabilities in Danfoss Refrigeration Controllers
Summary
Team82 reveals multiple vulnerabilities in the Danfoss AK-SM 800A refrigeration controller's embedded web interface, including a hidden code-of-day authentication bypass, a command injection for remote code execution, and an Nginx configuration injection. The team disclosed the issues to Danfoss, who released firmware R4.3.1; customers are advised to upgrade and avoid exposing management interfaces to the Internet. The report highlights how insecure web services in internet-facing CPS can enable powerful attack chains.