A code injection vulnerability has been discovered in the Robot Operating System (ROS) 'rostopic' command-line tool, affecting ROS distributions Noetic Ninjemys and earlier. The vulnerability lies in the 'hz' verb, which reports the publishing rate of a topic and accepts a user-provided Python expression via the --filter option. This input is passed directly to the eval() function without sanitization, allowing a local user to craft and execute arbitrary code.