Renowned Chinese jailbreak developer team, Pangu, has recently uncovered numerous iOS 8.4.1 kernel vulnerabilities found in 'AppleHDQGasGaugeControl' and also detailed the patch updates released by Apple in iOS 9 to fix these vulnerabilities, in a recent blog post. The same team had earlier demonstrated a functional iOS 8.4.1 jailbreak at the HackPwn2015 security conference.

Describing the three vulnerabilities used in iOS 8.4.1 jailbreak, Windknown, who is a veteran member of the Pangu team, writes:

When auditing iOS kernel executable, we found that the code quality of com.apple.driver.AppleHDQGasGaugeControl is very bad. In this blog, we will disclose 3 vulnerabilities in this kernel extension on the latest public iOS (version 8.4.1). More importantly, one of these bugs is a perfect heap overflow vulnerability that allows us to defeat all kernel mitigations and gain code execution in the kernel, just by exploiting this single vulnerability.

More about iOS 8.4.1 jailbreak Fake Evasi0n iOS 8.4.1 jailbreak released: Do not download

Further elaborating on the iOS 8.4.1 kernel vulnerabilities that have been patched up in iOS 9, the jailbreak developer clarifies that Apple has already fixed two out of three vulnerabilities in iOS 9 beta 5. In other words, it means the exploits used in iOS 8.4.1 jailbreak will no longer work with iOS 9.

With Apple expected to roll out iOS 9 Gold Master (GM) build to developers sometime after the iPhone 6s launch event on 9 September, it is almost certain that the public build or final release of iOS 9 should come out by next week. Furthermore, it is highly-speculated that the Pangu team could indeed release the next iOS jailbreak for iOS 8.4.1, given its recent revelation about which iOS 8.4.1 jailbreak exploits are patched up by Apple in iOS 9.

[Source: iPhone Hacks]