Apple Releases macOS Big Sur 11.3.1 With Fixes for WebKit Security Issues

Alongside iOS 14.5.1 and watchOS 7.4.1, Apple today also released macOS Big Sur 11.3.1, which the company says "provides important security updates".

macOS Big Sur Feature Purple
According to the full security notes for the release, it addresses a memory corruption issue and an integer overflow in WebKit that could both be exploited using maliciously crafted web content. Apple says it aware of a report that these issues may have been actively exploited, so users are advised to upgrade immediately.

Related Forum: macOS Big Sur

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Top Rated Comments

Anthony Sullivan Avatar
57 months ago
Do these small point updates really need to be gigabytes in size, take 50+ minutes to install (even on my Macs with SSDs), and push the OS build number? It's like installing a whole new version of macOS each time. Seems inefficient and likely to contribute to SSD wear.
Score: 16 Votes (Like | Disagree)
sirozha Avatar
57 months ago
3.30 GB for me on the M1 MacBook Air. Really Apple? 3.3 GB for a Webkit bug?
Score: 12 Votes (Like | Disagree)
GigabitEthernet Avatar
57 months ago
Will they ever fix AirPods audio switching? It is still broken
Score: 10 Votes (Like | Disagree)
doboy Avatar
57 months ago
Apple, shape up! Every recent updates have been followed up by .1 release about a week later. And more often then not, it’s due to something Apple screwed up and not security related.
Score: 8 Votes (Like | Disagree)
Jerry Fritschle Avatar
57 months ago

3.30 GB for me on the M1 MacBook Air. Really Apple? 3.3 GB for a Webkit bug?
Any changes to the Sealed System Volume appear to constrain the minimum size of a delta update.
Score: 5 Votes (Like | Disagree)
Populus Avatar
57 months ago
Don’t get me wrong, I’m glad Apple addressed a security flaw with a new update, but as others said on the iOS 14.5.1 post, didn’t Apple discover this over the two months of the beta? I made a clean install hoping 11.3 would last a while... I could have waited a week before making this clean install
Score: 5 Votes (Like | Disagree)