Apple Accidentally Unpatches Vulnerability, Leading to New iOS 12.4 Jailbreak

Apple in iOS 12.4 mistakenly unpatched a vulnerability that was fixed in the iOS 12.3 update, leading to a new jailbreak available for iOS 12.4 devices, reports Motherboard.

Hackers discovered the vulnerability over the weekend and Pwn20wnd created a publicly available, free jailbreak that works on devices running the latest version of iOS or any version of iOS below iOS 12.3.


Most jailbreak code is kept private to keep Apple from patching it, so this is the first time that a public jailbreak has been available in a while. It was apparently discovered when a user tested an older jailbreak on iOS 12.4 and found the patch had been reverted.

Security researcher Jonathan Levin told Motherboard that the accidental vulnerability also once again makes iPhone users vulnerable to a "100+ day exploit," referring to how long the bug has been around.

Ned Williamson from Google Project Zero said that the bug could be exploited to install spyware on a target ‌iPhone‌.
The researcher told Motherboard that "somebody could make a perfect spyware" taking advantage of Apple's mistake. For example, he said, a malicious app could include an exploit for this bug that allows it to escape the usual iOS sandbox--a mechanism that prevents apps from reaching data of other apps or the system--and steal user data.

Another scenario is a hacker including the exploit in a malicious webpage, and pairing it with a browser exploit, according to the researcher.
A third security researcher, Stefan Esser said that people should be careful what apps they download from the App Store right now. "Any such app could have a copy of the jailbreak in it," he wrote on Twitter.

Multiple users have confirmed that the jailbreak works and that their devices have been jailbroken using the new software. Apple has not commented on how or why the vulnerability was unpatched, but the company will likely have a fix available soon.

Top Rated Comments

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16 weeks ago

Honest question... do people still really jailbreak like that? Like, how big is the jailbreak community now?

I love questions like that. Yeah, the community is quite big, the jailbreak subreddit has over 300k subscribers and after last couple of releases it seems to be gathering some popularity.

Stock iOS 12 is great, but jailbreaking it is a no-brainer for me, especially when we can jailbreak the newest and signed version (which is a very rare opportunity)
I can tell you why I jailbreak all my iOS devices (SE and two X's)

- You can get real split screen multitasking with the https://www.idownloadblog.com/2019/04/23/pullover-pro/

- You can have ANY app on the CarPlay screen with https://www.redmondpie.com/carbridge-for-ios-12-jailbreak-released-lets-you-use-any-app-with-carplay/

- You can get all iPhone X gestures on older devices without any lags, bugs, with the https://www.idownloadblog.com/2019/03/18/neptune-for-iphone/

- You can have customizable Answering machine, record messages to the device and even set different greetings for different callers with https://www.idownloadblog.com/2018/08/23/answeringmachine-x/

- You can get rid of the full screen calling screen which users have been asking for ages with https://www.idownloadblog.com/2019/03/06/callbar-xs-brings-everyones-favorite-phone-call-centric-jailbreak-tweak-to-ios-12/

- You can stack icons together instead of using folders which looks extremely cool with https://www.idownloadblog.com/2018/12/03/zenith/

- You can get amazing gestures in app switcher screen with https://www.idownloadblog.com/2019/05/04/gesto/

- You can get the grid switcher from iPad in your iPhone with https://www.idownloadblog.com/2019/03/11/newgridswitcher/

- You can have custom shortcuts on lockscreen with the https://www.idownloadblog.com/2018/04/20/jumper/

- You can write notes on your lockscreen with the https://www.idownloadblog.com/2018/08/30/notepad/

- And hundreds of small things

Jailbreaking is not only about some themes, you can really get the 100% from your iPhones instead of the 60% or less that Apple gives you.
My jailbroken SE can do more than stock XS (without any performance issues) and that is not an exaggeration

I think that now is an amazing opportunity to try jailbreaking, you have nothing to lose. If anything happens (which is extremely unlikely because jailbreaks now aren't permanent/untethered) you can easily restore your device to the newest stock iOS version with iTunes and forget about everything
Rating: 30 Votes
16 weeks ago
I really wish that I had the surplus of time that hackers always seem to have.
Rating: 20 Votes
16 weeks ago
Honest question... do people still really jailbreak like that? Like, how big is the jailbreak community now?
Rating: 16 Votes
16 weeks ago

I wish Apple was on its game, but alas, no. It's a company spread too thin, governed by greedy hand-wringers.

Yes yes, and Apple is doomed and Steve is rolling in his grave like a gas station hotdog
Rating: 13 Votes
16 weeks ago
I'm surprised this regression happened. This points to a breakdown in product management discipline, which in general is a bad sign.
Rating: 12 Votes
16 weeks ago
I wish Apple was on its game, but alas, no. It's a company spread too thin, governed by greedy hand-wringers.
Rating: 11 Votes
16 weeks ago
"Unpatched" - There's a new one for the lexicon.
Rating: 9 Votes
16 weeks ago

Cant figure out why anyone would need a jailbreak anymore...

So they can install apps that Apple deems inappropriate for the app store...

You know, legitimate apps like Kodi and Retroarch...

Not to mention being able to customize their own devices any way they see fit.
Rating: 7 Votes
16 weeks ago
This is pretty ridiculous on Apple's part. I understand Apple develops parallel versions of iOS (12.3, 12.4, etc.) concurrently to reduce development time, but having one team not communicate with the other seems silly.
Rating: 5 Votes
16 weeks ago
Cough when does apple do anything *accidentally*
Rating: 5 Votes

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