Apple today released macOS Big Sur 11.6, the sixth major update of the Mac operating system. The release of Big Sur 11.6 comes a month after the release of macOS Big Sur 11.5.2.
The macOS Big Sur 11.6 update is free and can be downloaded on all compatible Macs using the Software Update section of System Preferences.
Apple’s release note indicates macOS Big Sur 11.6 includes security fixes and is recommended for all users. Apple also has released security update 2021-005 for macOS Catalina. Both updates fix an issue that allows a maliciously crafted PDF to execute code. Apple says that it is aware that this bug may have already been actively exploited.