iOS 18.3.1 brings critical fixes for iPhone: 4 key things you should know before updating

Apple has released a brand-new update for iPhones: iOS 18.3.1. Unlike typical iOS, iPadOS, and macOS updates that introduce new features, this update focuses on critical bug fixes and security improvements. It is an important update that all owners of compatible devices must download, and Apple states that it is recommended for all users. Here are four things you need to know about the iOS 18.3.1 update.

Why is the iOS 18.3.1 update important?

Apple explains in its release notes that this update fixes an issue where a physical attack could disable USB Restricted Mode on a locked device. In fact, Apple is aware of a report indicating that this vulnerability may have been exploited. It describes the attack as extremely sophisticated and targeting specific individuals. To address this, the update includes improved state management to fix an authorisation issue.

What is the name of this vulnerability, and who discovered it?

The vulnerability is identified as CVE-2025-24200. It was discovered by Bill Marczak of The Citizen Lab at The University of Toronto’s Munk School.

Which devices are eligible for this update?

This update is available for the following devices:

iPhone: iPhone XS and later, meaning all models from the iPhone XS to the latest iPhone 16 series.

iPad: iPad Pro 13-inch, iPad Pro 12.9-inch 3rd generation and later, iPad Pro 11-inch 1st generation and later, iPad Air 3rd generation and later, iPad 7th generation and later, and iPad mini 5th generation and later

How to download this update

To install iOS 18.3.1 on your supported iPhone: