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iOS 12.4.2 Provides Important Security Fix to Older iOS Devices

If you have an iOS device that can run iOS 12 but not iOS 13, Apple has a security fix for you. iOS 12.4.2 eliminates a vulnerability that could allow a remote attacker to cause an “unexpected application termination or arbitrary code execution,” exactly like Apple’s recent Mac-focused security updates (see “macOS Mojave 10.14.6 Supplemental Update 2,” 27 September 2019 and “Security Update 2019-005 (High Sierra and Sierra),” 27 September 2019). You can get the update, which clocks in at 77.7 MB on an iPhone 5s, in Settings > General > Software Update or through iTunes.

iOS 12.4.2 release notes

It’s a little unusual for Apple to release updates to versions of iOS other than the current one. But the fact that this vulnerability, which was identified by Google Project Zero, affects both macOS and iOS, and allows a remote attack, suggests that it may be a particularly ugly bug.

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Comments About iOS 12.4.2 Provides Important Security Fix to Older iOS Devices

Notable Replies

  1. “lots of people are likely still running iOS 12”

    Yes, but how do we get this update? iTunes and iOS only offer me 13.x (iTunes offers me 13.1; iOS offers me 13.1.1). Are they updating 12.4.x just to tease us :wink: or is it only available for a iPhone 5s (which you mentioned, but in a way that sounds like it should be available for other ones, too)?

    Is there some trick to get the 12.4.2 option? Thanks!

  2. Oh good question. I only checked on that iPhone 5s since it was the only iOS 12 device I had around at that moment, but Tonya’s home now with her devices. Checking… Yep, you’re right, iOS 12 devices that can go to iOS 13 are showing iOS 13.1.1 as the only available update. I’ll address this in the article.

  3. Thanks! Darn, Apple. ;-(

  4. Same issue as described below

    Last night I updated my iPad Air to iOS 12.4.2. (The iPad can’t run iOS 13)

    I don’t want to upgrade my iPhone to iOS 13 UNTIL I replace my iPad. I don’t want to operate in two different User interfaces on the 2 devices

    I just looked at General / Software Update on the iPhone and 12.4.2 was not an option

    My question: Is there an easy way to update the iPhone to 12.4.2??

  5. There is NO way to update the iPhone to 12.4.2 if it can run iOS 13.x. Only devices that can run iOS 12.x but cannot run iOS 13.x (namely, for the iPhone, the 5s, 6, and 6+) can install 12.4.2.

  6. GV

    Rats! I don’t want to upgrade to 13.1 until I have had an opportunity to see how works on older iPhones (I have a 6S that I bought new in January. . .)

  7. Similar here. Don’t want to upgrade iPad Air 2 because iPhone 6 can’t be upgraded to 13.
    So I’m sort of stuck between a rock and a hard place. I really hate Apple for policies like this. :angry:

  8. There are probably legitimate technical reasons. But the no option on upgrades is bad imo


  9. So all the Mail bugs are not limited to iPad Air 2? Eg count of unread in upper left corner while reading? Order of unread in the queue? Delete icon graying out? Messages changing back to unread after being read?

  10. I’m downloading it on my no-sim iPhone 6.

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