Crayfish is a collection of Islandora 8 microservices, one of which, Homarus, provides FFmpeg as a microservice. Prior to Crayfish version 4.1.0, remote code execution may be possible in web-accessible installations of Homarus in certain configurations. The issue has been patched in "islandora/crayfish:4.1.0". Some workarounds are available. The exploit requires making a request against the Homarus's "/convert" endpoint; therefore, the ability to exploit is much reduced if the microservice is not directly accessible from the Internet, so: Prevent general access from the Internet from hitting Homarus. Alternatively or additionally, configure auth in Crayfish to be more strongly required, such that requests with "Authorization" headers that do not validate are rejected before the problematic CLI interpolation occurs.