Apple Stops Signing iOS 15.4 Following iOS 15.4.1 Release, Downgrading No Longer Possible

Following the March 31 release of iOS 15.4.1, Apple has stopped signing iOS 15.4, the previously available version of iOS that came out earlier in March. As iOS 15.4 is no longer being signed, it is not possible to downgrade to that version of iOS once you've installed iOS 15.4.1.

iOS 15
Apple routinely stops signing older versions of software updates after new releases come out in order to encourage customers to keep their operating systems up to date, so it is not unusual that iOS 15.4 is no longer being signed.

iOS 15.4 was a major update featuring support for unlocking an iPhone while wearing a mask, new emoji characters, Universal Control on the iPad, and tons more.

iOS 15.4.1 added a fix for a battery drain issue on the ‌iPhone‌, but more importantly, it addressed AppleAVD issue that could allow an application to execute arbitrary code with kernel privileges. Apple said this exploit may have been actively exploited, so it is a good idea to update to iOS 15.4.1 if you have not done so already.

Apple has also stopped signing tvOS 15.4 and HomePod 15.4 software.

Related Forum: iOS 15

Popular Stories

iPhone 16 Pro Sizes Feature

iPhone 16 Series Is Just Two Months Away: Everything We Know

Monday July 15, 2024 4:44 am PDT by
Apple typically releases its new iPhone series around mid-September, which means we are about two months out from the launch of the iPhone 16. Like the iPhone 15 series, this year's lineup is expected to stick with four models – iPhone 16, iPhone 16 Plus, iPhone 16 Pro, and iPhone 16 Pro Max – although there are plenty of design differences and new features to take into account. To bring ...
macbook pro january

Best Buy's Black Friday in July Sale Takes Up to $700 Off M3 MacBook Pro for Members

Monday July 15, 2024 11:05 am PDT by
Best Buy's "Black Friday in July" sale is in full swing today, and in addition to a few iPad Air discounts we shared earlier, there are also some steep markdowns on the M3 MacBook Pro. You will need a My Best Buy Plus or Total membership in order to get some of these deals. Note: MacRumors is an affiliate partner with Best Buy. When you click a link and make a purchase, we may receive a small...
ipaos 18 image playground

Apple Releases First iOS 18 and iPadOS 18 Public Betas

Monday July 15, 2024 1:16 pm PDT by
Apple today provided the first betas of iOS 18 and iPadOS 18 to public beta testers, bringing the new software to the general public for the first time since the Worldwide Developers Conference in June. Apple has seeded three developer betas so far, and the first public beta includes the same content that's in the third developer beta. Subscribe to the MacRumors YouTube channel for more videos. ...
maxresdefault

Apple's AirPods Pro 2 vs. Samsung's Galaxy Buds3 Pro

Saturday July 13, 2024 8:00 am PDT by
Samsung this week introduced its latest earbuds, the Galaxy Buds3 Pro, which look quite a bit like Apple's AirPods Pro 2. Given the similarities, we thought we'd compare Samsung's new earbuds to the AirPods Pro. Subscribe to the MacRumors YouTube channel for more videos. Design wise, you could potentially mistake Samsung's Galaxy Buds3 Pro for the AirPods Pro. The Buds3 Pro have the same...
Beyond iPhone 13 Better Blue Face ID Single Camera Hole

10 Reasons to Wait for Next Year's iPhone 17

Monday July 8, 2024 5:00 am PDT by
Apple's iPhone development roadmap runs several years into the future and the company is continually working with suppliers on several successive iPhone models simultaneously, which is why we sometimes get rumored feature leaks so far ahead of launch. The iPhone 17 series is no different – already we have some idea of what to expect from Apple's 2025 smartphone lineup. If you plan to skip...
Generic iOS 18 Feature Real Mock

Apple Seeds Revised Third Betas of iOS 18 and iPadOS 18 to Developers

Monday July 15, 2024 10:09 am PDT by
Apple today seeded updated third betas iOS 18 and iPadOS 18 to developers for testing purposes, with the software coming a week after Apple initially released the third betas. Registered developers are able to opt into the betas by opening up the Settings app, going to the Software Update section, tapping on the "Beta Updates" option, and toggling on the ‌iOS 18/iPadOS 18‌ Developer Beta ...

Top Rated Comments

Danfango Avatar
30 months ago

Endless updates...more bugs...RedHat LinMac 2000
How dare they inconvenience the user by fixing stuff, protecting the user and improving the product that the user is complaining about!
Score: 8 Votes (Like | Disagree)
vanylapep Avatar
30 months ago
It's a trap.

Once you update your phone to 15.4.1, Xcode 13.2.1 won't allow you to deploy to your phone because it only supports 15.4.0. So you update to Xcode 13.3 but your macOS won't allow it because you're on macOS 11.3 but Xcode 13.3 requires macOS 12.0. So you gota buy a new Macbook.
Score: 7 Votes (Like | Disagree)
Mr. Dee Avatar
30 months ago
I finally upgraded to iOS 15.4.1 from iOS 14.8.1 on my iPhone X and 2017 iPad Pro 12.9. I couldn’t stand the nagging at work anymore. The iPhone X feels like a new phone with the upgrade and I do feel the speed difference. On the iPad there isn’t really not much that feels new but its there. The only other iOS device I have not updated because it failed a couple times is my iPhone 6s.

I took that as a warning sign and leave it be. The watchOS 8.5.1 update failed a couple times, but I just put my S3 next to my X before going to bed and updated the next morning.

So, things are going well otherwise. See you back here next year with iOS 16.
Score: 2 Votes (Like | Disagree)
_Spinn_ Avatar
30 months ago
I'm glad Apple does what it can to stop OS fragmentation.
Score: 2 Votes (Like | Disagree)
winxmac Avatar
30 months ago

I finally upgraded to iOS 15.4.1 from iOS 14.8.1 on my iPhone X and 2017 iPad Pro 12.9. I couldn’t stand the nagging at work anymore. The iPhone X feels like a new phone with the upgrade and I do feel the speed difference. On the iPad there isn’t really not much that feels new but its there. The only other iOS device I have not updated because it failed a couple times is my iPhone 6s.

I took that as a warning sign and leave it be. The watchOS 8.5.1 update failed a couple times, but I just put my S3 next to my X before going to bed and updated the next morning.

So, things are going well otherwise. See you back here next year with iOS 16.
I was on iOS 14.8 then upgraded to iOS 15.4 then I saw that iOS 15.3 RC was still signed at that time so I downgraded to it and still on it at the moment... Upgraded and downgraded using IPSW through iTunes...

In the company I work at, I also receive email notification about needing to go to the latest version otherwise access to company resource will not work... I don't have a work-provided phone and I just decided to upgrade...

Also, note to Apple, re-sign the last update of previous versions so if someone cannot afford to buy a newer model, the device they currently have will still be at least useable although with limited app support...
Score: 2 Votes (Like | Disagree)
leicaman Avatar
30 months ago
When the version that they stop signing has two zero day flaws, there's an inescapable reason to stop letting people downgrade to it.
Score: 2 Votes (Like | Disagree)