Apple hastily adds security patches in macOS Big Sur 11.3.1, watchOS 7.4.1


Apple Security Jacket
There are critical security patches for Mac and Apple Watch.
Photo: Jim Merithew/Cult of Mac

Mac users can now download macOS Big Sur 11.3.1, a security-themed update to the version released a week ago. It closes security holes that Apple knows were exploited by hackers.

Monday was a busy day for updates. Apple also released watchOS 7.4.1 with one of the same security fixes. And it introduced iOS 14.5.1 and iPadOS 14.5.1 to take care of an App Tracking Transparency bug, and fix security bugs.

Security changes in macOS Big Sur 11.3.1, watchOS 7.4.1

macOS Big Sur 11.3.1 takes care of a couple of serious bugs. According to Apple’s notes for the new version, both are in WebKit and opened security holes for hackers. And this isn’t theoretical. “Apple is aware of a report that this issue may have been actively exploited,” notes the company about each bug. Only installing the new version closes them.

WebKit is used across Apple devices, and this fix also had to be patched in the new iPhone and iPad software updates, according to their release notes. And one of the bugs needed to be taken care by Monday’s Apple Watch update too.

macOS Big Sur 11.3.1 doesn’t include additional features. Nor does watchOS 7.4.1. but they are still highly recommended.

Get these updates now

Anyone running macOS Mojave or later can get the latest version of macOS Big Sur via Software Update: Go to the Apple menu  > System Preferences, then click Software Update. Another option is to install the new version from the App Store.

And Monday’s Apple Watch update can be installed directly onto the wearable, as long as its connected to Wi-Fi. From the Settings app, just navigate to General > Software Update. Then tap Download and Install. Alternatively, this update can be installed from an iPhone by opening the Apple Watch app and going to My Watch > General > Software Update.


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