macOS 11.2.1 Big Sur Fixes MacBook Pro Charging Bug and sudo Vulnerability
Apple has released macOS 11.2.1 Big Sur to fix a single bug that prevented some 2016 and 2017 MacBook Pro models from charging. It appears that macOS 11.2 might actually have damaged these batteries; see “Apple Replacing Some Batteries in 2016 and 2017 MacBook Pro Models” (10 February 2021).
Despite the specificity of that fix, macOS 11.2.1 is available for all compatible Macs because it also eliminates three security vulnerabilities, including one that could enable a local attacker to exploit the Unix sudo utility to elevate their privileges.
Apple says the macOS 11.2.1 update is a 2.43 GB download, and it’s available only through Software Update. However, as with the macOS 11.2 update (see “macOS 11.2 Big Sur Improves Bluetooth, Squashes Bugs,” 1 February 2021), that size doesn’t match with the progress dialog on an M1-based MacBook Air, which reports that it’s downloading 3.35 GB of data. The same dialog on an Intel-based iMac reports the correct 2.43 GB download size. If you can shed any light on the discrepancy, let us know in the comments.
If you have a 2016 or 2017 MacBook Pro, we recommend installing macOS 11.2.1 right away to ward off any potential battery-related problems. Similarly, it’s worth installing quickly if you’re worried about the sudo bug due to a rogue Unix expert having physical access to your Mac. Otherwise, you should be able to delay installing this update until it has been out for a while and it’s a convenient time for you.
Now that there’s news of macOS 11.2 potentially damaging batteries in 2016 and 2017 MacBook Pro models, I’ve updated this article to recommend installing 11.2.1 immediately if you have one of those Macs.
For what it’s worth, it also fixed the “hold charge” issue I was having on my 2019 16" MacBook Pro. Previously I’d selected the option to optimize charging but the charge was always 100%. Since installing the latest update, the battery charging is holding at a lower level as expected.
Apple took back my new M1 Macbook Air for same reason
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