Siemens RuggedCom Rugged Operating System (ROS) before 3.12, ROX I OS through 1.14.5, ROX II OS through 2.3.0, and RuggedMax OS through 4.2.1.4621.22 use hardcoded private keys for SSL and SSH communication, which makes it easier for man-in-the-middle attackers to spoof servers and decrypt network traffic by leveraging the availability of these keys within ROS files at all customer installations.
http://www.us-cert.gov/control_systems/pdf/ICSA-12-354-01.pdf