macOS Big Sur 11.6.3 and Security Update 2022-001 Catalina
Apple has released macOS Big Sur 11.6.3 and Security Update 2022-001 for macOS 10.15 Catalina, patching seven security vulnerabilities in Big Sur and five in Catalina. Both updates address a buffer overflow issue with improved memory handling to prevent malicious applications from executing arbitrary code with kernel privileges, improve PackageKit validation to prevent access to restricted files, and improve checks in TCC (Transparency, Consent, and Control) to prevent applications from bypassing certain privacy preferences. We recommend installing the Big Sur update soon, in particular, since Apple says it’s aware of one of the fixed vulnerabilities actively being exploited in the wild. If you notice any problems after updating, please let us know in the comments. (Free, various sizes, Big Sur release notes, Catalina release notes, macOS 11 and 10.15)
Since installing this Catalina security update on my Macbook Pro, the machine had taken to shutting itself down at some point after I put it to sleep.
Issue now being reported elsewhere: MacBook Air Reboots/Restarts After Catalina Security Update 2022-001 | MacRumors Forums
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