October 1, 2025, 6:31 am | Read time: 2 minutes
Since September, iPhone XS, XS Max, and XR can no longer update to the latest iOS version. Therefore, alongside iOS 26, Apple has released iOS 18.7 for older models, which contains the same security content. Just a few weeks later, an update in the form of iOS 18.7.1 follows, bringing further improvements.
Major Security Flaw Closed
While Apple had to fix bugs with iOS 26.0.1 that it caused with iOS 26, it was able to focus on the essentials with 18.7.1. The update addresses a vulnerability in the FontParser of the iPhone operating system. This component is responsible for processing and providing font files such as TrueType or OpenType fonts.
An “out-of-bounds write” error allowed attackers to write data outside the intended memory area. Maliciously manipulated fonts could, in the worst case, lead to app crashes and memory errors. Apple claims to have discovered the issue (CVE-2025-43400) itself and resolved it with an additional memory area check.
iOS 26.0.1 Is Here–What’s in the iPhone Update
Apple Closes FBI Backdoor in iPhone
Should You Install iOS 18.7.1 Right Away?
TECHBOOK generally recommends installing available patches for security vulnerabilities. Although iOS 18.7.1 is just a minor “X.X.1” update with a single patch, it is particularly important as it resolves a significant memory issue.
The small interim versions rarely lead to new errors but focus on fixing existing problems. Given the manageable file size of a few hundred megabytes, installation is recommended without hesitation.
Even Update Skeptics Benefit
iOS 18.7.1 is available for iPhone XS, XR, and newer. This means that older models that can no longer update to iOS 26 are also protected. But owners of iPhone 11 and newer can also install the update if they haven’t yet installed iOS 26. So, those who want to wait until Apple fixes all the bugs in the latest iOS version can stay safe with 18.7.1.
Also read: After Updating to iOS 26 – Apple Blocks Downgrade to Older Version
Simultaneously with the iPhone update, iPadOS 18.7.1 with identical security content has been released. It is compatible with iPad Pro 11-inch 1st generation and newer, iPad Pro 12.9-inch 3rd generation and newer, iPad Pro 13-inch, iPad Air 3rd generation and newer, iPad 7th generation and newer, and iPad mini 5th generation and newer.