The source code for a key piece of the iPhone's core software, called iBoot, has appeaded on GitHub, bringing excitement to entusiasts envisioning a "liberated" iOS booted on generic arm boards.

iBoot is the code that runs on the iPhone before iOS gets started. It's the part of iOS that ensures a trusted boot of the iPhone's operating system.

Security researcher Jonathan Levin, who has written books on iOS and macOS, underlibed the significance of the leaked code, speaking to Motherboard. "iBoot is the one component Apple has been holding on to, still encrypting its 64-bit image," Levin said. "And now it's wide open in source code form."

https://motherboard.vice.com/en_us/article/a34g9j/iphone-source-code-iboot-ios-leak

Levin claims that the code is real and comes from the older iOS 9. However, it could be interesting to security researchers and hackers looking for holes in Apple's mobile operating system. Any iBoot vulnerabilities discovered could lead to new jailbreaks, and even ways to decrypt the iPhone. The leak could also allow hackers to emulate iOS on non-Apple platforms. Circumventing the lock screen protection of an iPhone, as hackers had demonstrated in the past, could not be succeful in latest iPhones, which have a Secure Enclave Processor on board.

In a statement, Apple said, "Old source code from three years ago appears to have been leaked, but by design the security of our products doesn't depend on the secrecy of our source code. There are many layers of hardware and software protections built into our products, and we always encourage customers to update to the newest software releases to benefit from the latest protections."

Apple has also issued a DMCA takedown notice for the code and Github and has disabled the repository that was hosting it.