KnockKnock is a free, open-source tool that uncovers persistently installed software on macOS, helping to generically reveal malware. It scans known locations where persistent software or malware may be installed, and provides detailed information about each item, including its hash, size, plist, and signed status. KnockKnock also integrates with VirusTotal to retrieve information about the files and allows users to submit unknown files for analysis. The tool provides a user-friendly interface to display the results, with options to filter out signed Apple and whitelisted items, and to save the findings as a JSON file. KnockKnock can also be run via the command line, allowing for programmatic deployment and execution. Overall, KnockKnock is a valuable tool for macOS users to detect and analyze persistently installed software and potential malware on their systems.