ScanCode.io command injection in docker image fetch process

Summary

ScanCode.io is a server to script and automate software composition analysis with ScanPipe pipelines. Prior to version 32.5.1, the software has a possible command injection vulnerability in the docker fetch process as it allows to append malicious commands in the `docker_reference` parameter. In the function `scanpipe/pipes/fetch.py:fetch_docker_image` the parameter `docker_reference` is user controllable. The `docker_reference` variable is then passed to the vulnerable function `get_docker_image_platform`. However, the `get_docker_image_plaform` function constructs a shell command with the passed `docker_reference`. The `pipes.run_command` then executes the shell command without any prior sanitization, making the function vulnerable to command injections. A malicious user who is able to create or add inputs to a project can inject commands. Although the command injections are blind and the user will not receive direct feedback without logs, it is still possible to cause damage to the server/container. The vulnerability appears for example if a malicious user adds a semicolon after the input of `docker://;`, it would allow appending malicious commands. Version 32.5.1 contains a patch for this issue. The `docker_reference` input should be sanitized to avoid command injections and, as a workaround, one may avoid creating commands with user controlled input directly.