Apple finally patched a vulnerability that leads to the development of a publicly available jailbreak code with a new update, Monday. The company has previously patched the said vulnerability in iOS 12.3 but they unintentionally unpatched it in iOS 12.4.
The new update, iOS 12.4.1, patches the earlier vulnerability which has allowed Pwn20wnd, a known jailbreak creator, to create a publicly available free jailbreak that works on devices running the latest version of iOS or any version of iOS below iOS 12.3.
In a security update post, Apple said that it fixed a kernel vulnerability that could have allowed an attacker to execute code on an iPhone or iPad with the highest level of privileges.
Apple justified their silence on the issue by saying that they avoid making comments about security flaws before they finish their investigations.
“For our customers’ protection, Apple doesn’t disclose, discuss, or confirm security issues until an investigation has occurred, and patches or releases are available. Recent releases are listed on the Apple security updates page,” they said.
Apple further said that “malicious application may be able to execute arbitrary code with system privileges” because of the vulnerability and “use after free issue was addressed with improved memory management” in collaboration with Google Project Zero’s Ned Williamson.
The jailbreak code went public to draw Apple’s attention to the vulnerability
Jailbreaking has been a problem for Apple for the last few years. It is the process by which hackers creates a privilege escalation on an Apple device which effectively removes software restrictions imposed by iOS. It is typically done using kernel patches in order to allow unauthorized and root installation of applications that are not available in the official Apple App Store.
Because of the unintentional resurfacing of the vulnerability that was supposedly patched before the iOS 12.4, Pwn20wnd, was able to develop a code that would help essentially anyone who knows to use it to bypass Apple’s restrictions and root their iOS devices, allowing them to gain high privileges with their phones.
Pwn20nd has posted the assets for the publicly available jailbreak codes in a Github forum with multiple updates, and while offers the open-source code for free, he is asking people for donations through his Paypal and Patreon accounts.
The jailbreak created by the hacker was interesting during the time it was released. Most of the jailbreak codes are developed and kept in private in order to prevent Apple from noticing it and delaying the company to patch the vulnerability being exploited by the jailbreak. This time, however, the hacker decided to make the jailbreak code public. The jailbreak codes were discovered when a user tried to reuse an old iOS 12.4 and found that the jailbreak has been reverted.
The reason that the hacker decided to make the code public is for him to draw the attention of Apple regarding the re-emergence of the vulnerability and to send a message to the company that they need to patch it as soon as possible. This could possibly be true as Apple acknowledged the help of Pwn20wnd in its security update and thanked the hacker for his assistance in patching the zero-day.
“We would like to acknowledge @Pwn20wnd for their assistance,” Apple said in the security update page. It is still unclear what exactly the contributions of the hacker are.
Public jailbreak codes are dangerous
While the jailbreak code created by the hacker is helpful to those who want to use it, security experts previously said that it is dangerous as well. They noted that since the code is publicly available, many applications that are downloadable from the App Store could also smuggle the code into a target phone, Stefan Esser, a cybersecurity expert, explained.
“I hope people are aware that with a public jailbreak being available for the latest iOS, 12.4 people must be very careful what Apps they download from the Apple AppStore. Any such app could have a copy of the jailbreak in it,” his tweet reads.
Many users have already confirmed that the jailbreak developed by Pwn20wnd works, and many devices have already been jailbroken by exploiting the accidental bug from iOS 12.4 update.
Meanwhile, the iPhone maker said that the new update is available to iPhone 5s and later, iPad Air and later, and iPod touch 6th generation.