190827 apple update
Image Credit: AFP

San Francisco: Apple has finally fixed an "unpatched" bug in the latest iOS update that had left its most up-to-date iPhones vulnerable to hacking risk.

The new update "12.4.1" introduces a fix for vulnerability in which, according to Apple, "a malicious application may be able to execute arbitrary code with system privileges".

"We would like to acknowledge @Pwn20wnd for their assistance," said Apple.

A security researcher that goes by the name of "Pwn20wnd" published a jailbreak for the earlier iOS 12.4 update.

Apple reportedly unpatched a bug in the latest iOS update 12.4 that it had fixed in the earlier iOS 12.3 update -- leaving its devices vulnerable to cyber criminals.

Jailbreaking an iPhone lets people customize their iOS devices and run unsupported apps. Apple never allows unsupported apps on its iOS platform, which makes its devices extra secure.

As a result of the unpatched bug, all iPhones running iOS 12.4 could be jailbroken.

Several iPhone users tweeted that they were successfully running the "jailbreak".

Apple recently announced to pay up to $1 million to security researchers for finding flaws and vulnerabilities as part of its bug bounty programme.