iOS 18.3.1 patches an 'extremely sophisticated attack' – and more

Yesterday, iOS 18.3.1 for iPhone dropped, and while the last few updates have been packed with new features — many related to Apple Intelligence — this one seems to be primarily a security update.

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And it’s an important one.

Pretty serious, but niche

The release notes are vague, mentioning that the update contains “important bug fixes and security updates and is recommended for all users.”

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However, a little digging into Apple’s security documents sheds more light on the update. It addresses a bug that makes use of “an extremely sophisticated attack” to “disable USB Restricted Mode on a locked device.” This is clearly a physical attack, requiring hands-on access to the iPhone, so it’s unlikely to impact the majority of users.

According to Apple, there’s evidence that this issue may have been exploited “against specific targeted individuals.”

So, while it’s pretty serious, it’s also very niche.

Behind-the-scene tweaks

As for any big user interface changes, you’re out of luck. These x.3.1 updates are almost exclusively behind-the-scenes tweaks. Those changes will likely be saved for iOS 18.4.

If you’re someone who doesn’t want or need Apple Intelligence — I’ve found that I get better battery life with it turned off — you might want to double-check that this update hasn’t turned it back on. I’ve heard from a few people who said that Apple Intelligence was re-enabled following the update.

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For those who do use Apple Intelligence and like the summarized notifications feature, note that you still cannot summarize news-related notifications. It’s disabled for specific news apps, and even disabling and re-enabling the feature to bring up the screen that allows you to choose how summarization works doesn’t fix this.

Resolved iOS 18.3 bugs

As for other iOS 18.3 bugs, iOS 18.3.1 may — or may not — bring relief. For example, the camera bug where the shutter button would go unresponsive seems to have been fixed. However, a keyboard bug where stickers aren’t working properly and many of them appear blank still persists.

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On the performance front, nothing has changed. I ran Geekbench before and after installing the update and saw no difference, which is in line with what I expected. While it’s too early to tell, I don’t anticipate much change in battery life either, unless Apple has squashed some bugs under the hood.

You have updating to do

Also released alongside iOS 18.3.1 were iPadOS 18.3.1 (and iPadOS 17.7.5 for those on older devices), MacOS 15.3.1 (along with MacOS 14.7.4 and 13.7.4 for older Macs), and visionOS 2.3.1.

So, you’ve got a lot of updating to do!

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If you’re waiting for iOS 18.4 to land — and it’s expected to be a big one, rolling out an upgraded Siri — you’ll have to wait a while. It’s not expected to arrive until sometime in April.