On Apple's Cloud Key Vault - and why it *might* actually be secure
There is a nice writeup on this at Lawfare . (TL;DR - holding on to keys in a safe way such that 3rd parties can also access them repeatedly without high potential for catastrophic loss is impossibly hard) ...Apple’s design intentionally solved the problems that come from exceptional access schemes by removing itself from the equation. Rather than providing an exceptional access solution, Apple took the radical step of destroying those keys in order to have an acceptable level of protection. [To] turn Apple’s Cloud Key Vault into an exceptional access mechanism....Apple would have to replace the HSM with one that accepts an additional message from Apple or the FBI—or an agency from any of the 100+ countries where Apple sells iPhones—saying “OK, decrypt,” as well as the user’s password. In order to do this securely, these messages would have to be cryptographically signed with a second set of keys, which would then have to be used as often as law enforcement ac...