Soft Serve is a self-hostable Git server for the command line. Prior to 0.7.5, it is possible for a user who can commit files to a repository hosted by Soft Serve to execute arbitrary code via environment manipulation and Git. The issue is that Soft Serve passes all environment variables given by the client to git subprocesses. This includes environment variables that control program execution, such as LD_PRELOAD. This vulnerability is fixed in 0.7.5.
The product constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command when it is sent to a downstream component.