Arr-pm is an RPM reader/writer library written in Ruby. Versions prior to 0.0.12 are subject to OS command injection resulting in shell execution if the RPM contains a malicious "payload compressor" field. This vulnerability impacts the `extract` and `files` methods of the `RPM::File` class of this library. Version 0.0.12 patches these issues. A workaround for this issue is to ensure any RPMs being processed contain valid/known payload compressor values such as gzip, bzip2, xz, zstd, and lzma. The payload compressor field in an rpm can be checked by using the rpm command line tool.