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Apple Patches Flaw That Enables 'unc0ver' iOS Jailbreak

Less than two weeks ago, the hacking community released a new tool called unc0ver that can jailbreak newer iPhones via a flaw in iOS; the latest version of iOS fixes the bug.

Michael Kan
 & Michael Kan Principal Reporter

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Apple has plugged a hole in iOS that can let you jailbreak your iPhone or iPad to install unsanctioned apps. 

The company’s patch is designed to address “unc0ver,” a jailbreaking tool released last month. The team behind the jailbreak found a software-based vulnerability in iOS 11 through iOS 13.5, which can be used to gain root access to Apple’s software. 

Such access can enable an iPhone owner to install and run apps not offered on the official iOS App Store. However, Apple moved quickly to fix the vulnerability, releasing a security update with iOS 13.5.1 that patches the flaw. 

A team member behind the unc0ver jailbreak confirmed Apple's fix patches the hole. As a result, users interested in using the jailbreak should keep their iPhones on iOS version 13.5. 

The unc0ver tool works by targeting a software-based vulnerability in the iOS kernel, which is one of the first programs to boot up on an iPhone. The tool itself is free for anyone to download.

However, the jailbreak requires the user to connect the iPhone to a Mac, Linux, or Windows machine and go through a dozen different steps to successfully run the exploit. (If you decide to try it, make sure you create a software backup.) The jailbreak also can’t be executed remotely, making it less effective for malicious hacking purposes. You can reverse the jailbreak as well. 

The hacking community developed unc0ver months after another jailbreaking tool called checkra1n hit the scene. But unlike unc0ver, checkra1n leverages a hardware-based vulnerability in the memory chips inside older iPhones, making the jailbreak unpatchable.

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About Our Expert

Michael Kan

Michael Kan

Principal Reporter

My Experience

I've been a journalist for over 15 years. I got my start as a schools and cities reporter in Kansas City and joined PCMag in 2017, where I cover satellite internet services, cybersecurity, PC hardware, and more. I'm currently based in San Francisco, but previously spent over five years in China, covering the country's technology sector.

Since 2020, I've covered the launch and explosive growth of SpaceX's Starlink satellite internet service, writing 600+ stories on availability and feature launches, but also the regulatory battles over the expansion of satellite constellations, fights with rival providers like AST SpaceMobile and Amazon, and the effort to expand into satellite-based mobile service. I've combed through FCC filings for the latest news and driven to remote corners of California to test Starlink's cellular service.

I also cover cyber threats, from ransomware gangs to the emergence of AI-based malware. In 2024 and 2025, the FTC forced Avast to pay consumers $16.5 million for secretly harvesting and selling their personal information to third-party clients, as revealed in my joint investigation with Motherboard.

I also cover the PC graphics card market. Pandemic-era shortages led me to camp out in front of a Best Buy to get an RTX 3000. I'm now following how the AI-driven memory shortage is impacting the entire consumer electronics market. I'm always eager to learn more, so please jump in the comments with feedback and send me tips.

The Best Tech I've Had:

  • My first video game console: a Nintendo Famicom
  • I loved my Sega Saturn despite PlayStation's popularity.
  • The iPod Video I received as a gift in college
  • Xbox 360 FTW
  • The Galaxy Nexus was the first smartphone I was proud to own.
  • The PC desktop I built in 2013, which still works to this day.

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