iOS 18.3.1: Apple fixes critical vulnerability in USB Restricted Mode

Apple has released an emergency update with iOS 18.3.1 and iPadOS 18.3.1 to correct a severe vulnerability which compromised the security of iPhone and iPad devices. This flaw allowed attackers to disable the USB Restricted Mode, a key feature for protection against unauthorized access via the USB port.

The problem has been identified as CVE-2025-24200 and was discovered by security researcher Bill Marczak of The Citizen LabAccording to Apple, the vulnerability was used in highly sophisticated attacks targeted at specific individuals, which highlights their seriousness.

What is USB Restricted Mode and why is it important?

El USB Restricted Mode It was implemented by Apple several years ago to Prevent unauthorized access via the USB port. This feature blocks USB communication if the device has been locked for a certain amount of time, preventing forensic or malicious tools from extract information without the user's consent.

This security mode has been a obstacle for government agencies and researchers who attempt to gain access to devices without the owner's permission. However, the recently discovered vulnerability allowed disabling this protection with a physical attack on locked devices.

CVE-2025-24200 Vulnerability Details

This vulnerability was found in the authentication system of iOS and iPadOS, allowing attackers to Disable USB Restricted Mode without having to enter the device unlock code. Apple has confirmed that this flaw had already been exploited in sophisticated attacks, although it has not revealed details about the affected victims.

El The discovery of this security flaw is due to The Citizen Lab, an organization known for analyzing the use of spyware such as Pegasus on iOS devices. These types of attacks They are usually aimed at high profile users, such as journalists, politicians and activists.

Affected devices and solution

To avoid this vulnerability all we have to do is update our iPhone to the latest version, in this case version 18.3.1. iOS 18.3.1 update is now available for a wide range of devicesincluding:

• iPhone XS and later models
• iPad Pro 13-inch, iPad Pro 12,9-inch (3rd generation) and later
• 11-inch iPad Pro (1st generation) and later
• iPad Air (3rd generation) and newer versions
• iPad 7th generation and later
• iPad mini (5th generation) and newer versions

Users can install the update accessing Settings > General > Software Update and following the on-screen instructions.

Other security improvements in iOS 18.3.1

In addition to the security patch for USB Restricted Mode, iOS 18.3.1 also fixes a few other important bugs:

• Siri voice input bug fix, which caused the keyboard to disappear when activated.
• Troubleshooting a bug in Apple Music, where audio playback continued even after closing the app.
• Improvements to application encryption, although Apple has indicated that some problems persist and that they will continue to work on future updates.

Apple strengthens the security of its ecosystem

Along with iOS 18.3.1 and iPadOS 18.3.1, Apple has also released updates for other systems:

• macOS 15 for Mac computers.
• watchOS 11 for Apple Watch smartwatches.
• visionOS 2 for Apple Vision Pro.

While these updates do not mention critical security vulnerabilities, they do incorporate General performance and stability improvements.

Security updates on iOS are essential to keep devices protected from malware. increasingly sophisticated threats. The vulnerability fixed in this release demonstrates the importance of keeping devices up to date, as exploits like this can be used in targeted attacks against specific users. If you haven't yet updated your iPhone or iPad, It is advisable that you do it as soon as possible to minimize any risk..