Thanks for the permissions fix - which does stop bsdtar from running endlessly. In /Applications/Parallels Toolbox.app/Contents/Resources/ToolboxCommon.bundle/Contents/MacOS/ToolboxCommon, there is a string tar -czf "%@" -s /.*/Report\.xml/g "%@" && curl -v -X POST -H "Content-Type: multipart/form-data" --form "data=@%@" %@ > "%@" && rm -f "%@" && rm -f "%@" I presume it's trying to send information about breakage or maybe usage to Parallels?? This appears to be the cause of the problem. Looks like Parallels need to wonder why this is failing in Catalina... perhaps a change of default shell?