Downloading the macOS Catalina 10.15.7 ISO is a common requirement for users looking to install the operating system on virtual machines like VirtualBox or VMware , or to create a bootable installer.
hdiutil create -o /tmp/Catalina -size 8500m -volname Catalina -layout SPUD -fs HFS+J macos catalina 10157 iso download new
hdiutil attach /tmp/Catalina.dmg -noverify -mountpoint /Volumes/Catalina Create the installation media: Downloading the macOS Catalina 10