Behind the Scenes of iOS Security

I found the talk (though I don't pretend to understand it all), video & slides are online if others are interested. Behind the Scenes with iOS Security Abstract - [LINK] Slides - [LINK] Video - [VIDEO]

For a really in-depth dive about the iOS class keys system he mentions I recommend this 2016 blackhat talk by Ivan Krstic (head of security at Apple): [VIDEO] (relevant portion starts at 6:56)

Given the way iCloud security works I'm not sure iCloud was breached at all [1]. Other reports seem to indicate that it was employees at Apple stores and third party resellers who had access to names, phone numbers and Apple IDs [2]. Presumably they would try to phish them later on. [1] [VIDEO] [2] [LINK]

It all boils down to what you see in the public. The FBI was trying to get Apple to create an iOS variant to extract data from a device, to the point where Tim Cook wrote a letter refusing to do so and was willing to fight it in court. In a similar fashion, Apple has given talks and white papers on iOS security. In tandem with these well documented white papers and talks discussing the internal functions of iOS, we haven't seen any well known or trivial exploits appear to surface that demonstrate flaws in them. In the case of the FBI fiasco, for example, we know that the FBI later paid Cellebrite for an exploit that allowed them to unlock the device. We don't know the details of how that happened, but the FBI had to reach out to an independent company and exploit an older device to do it. To be clear: if they were lying about the lengths they go to with encryption, on device security, and user trust, this story would have been different. The FBI would have already had a backdoor or been able to trivially break the device, or they would have complied and created an iOS variant to break in. All we know is what they stood their ground on, and the effort that was required for the FBI to get in. iOS 10 security white paper: [LINK] Talk about iOS security at Black Hat: [VIDEO]

There's a video of a presentation by Ivan Krstic (head of security engineering, Apple) at Black Hat from 2016 about iOS security: [VIDEO]

They do all sorts of device key exchange, if you haven't watched the talk at Black Hat I'd highly recommend it: [VIDEO] (link goes to beginning of Secure Enclave content, and later on in the talk he discusses iCloud which uses the SEP keys)

The Black Hat talk was really great: [VIDEO] (link is to SEP and on-device encryption, 22:30 is iCloud stuff) > I know they said they could have accessed that San Bernardino terrorist’s iCloud backup if only they had one. Not sure if they’ve change the security architecture since then. I actually think they have, the shooting was in 2015 and iOS 10 was released in 2016 and was first to have some of the features he talks about in the video.

Passwords are backed up but they are end to end encrypted. Check out Cloud Key Vault, it’s a pretty cool solution for keychain (password) backups designed for adversarial clouds. Unfortunately does not apply to regular iCloud backups or most other data. But a major step forward. [VIDEO]

[VIDEO] They take security for these things seriously. You can store data safely even in adversarial clouds.

That’s not the apple talk. Apple gave a talk specifically about hardware security in the iPhone. Edit: this one. [VIDEO] Edit 2: the question was asked at 47:20

Take a look at this blackhat talk from Apple's head of security Ivan Krstic, where he explains the mechanism they use to secure credentials stored in the cloud: [VIDEO]

Worth noting that Apple "gets away" with more in China than most: - iMessage, one of the only end-to-end encrypted messaging systems widely available in China. - iCloud Keychain, which they've designed to work securely on "adversarial clouds"[1] (Of course this may only be because not many people actually use these features versus WeChat...) [1] [VIDEO]

The apple security whitepaper is actually a decent place to start [LINK] There is also a blackhat talk from Ivan Krstic (one of the top security people at apple) where he goes surprisingly deep [VIDEO]

I tried 1Password but finally resolved to use iCloud keychain after watching this BlackHat 2016 video [VIDEO] . I mean as far as I already trust their OS nothing can really protect me from being spied by them if they are ill intentioned, so as long as they are serious and patch their security flaw on a timely manner I can live with that. Beside it come as a free plan if you don't need more than 5GB of iCloud storage. I'd figure using an external password manager just add another third party I need to trust and the fact that 1Password offer browser app interface (on top of native) don't reassure me in any way. Of course if I'd ever need to reassess my threat model because I can't trust Apple anymore, I will quit iCloud service at the same time as their OS and go full FOSS.

You may be interested in watching Ivan Krstić’s BlackHat talk[0], in which he details the security of the iCloud infrastructure. The use of physical one-way hash functions is involved. [0] [VIDEO]

>So I don't really understand how this can be said to be a hardware security token. No one claimed it's a hardware security token, but the private keys are stored in iCloud Keychain, which is end-to-end encrypted. Apple cannot access your private keys even if iCloud is compromised by an external attacker or employee. If you're curious about the security engineering, you should watch the "Synchronizing secrets" part of this Black Hat talk from 2016: [VIDEO] or you should read the "Synchronization security" section of the "About the security of passkeys" support doc: [LINK]

There have been several comments along the lines of: "Why should I trust apple and their security, but not that of a third-party web browser?" I don't have an answer for you. But I want to recommend this talk from 7 years ago: [VIDEO] That alone convinced me. Apple knows what it is doing when it comes to device security. Today, I trust them with my most sensitive data and sleep peacefully at night.

This is not just encryption in transit or simplistic client-side encryption. It is end-to-end encryption, where each device's key generation is handled by your phone's Secure Enclave. This article is a decent starting point in terms of what Advanced Data Protection is: [LINK] If you want a deeper dive into the security engineering of iCloud Keychain, the second half of this Blackhat talk by Apple's head of Security Engineering & Architecture (SEAR) is really great: Synchronizing secrets: [VIDEO]

You shouldn't include Apple in this. As of macOS Tahoe, the FileVault key you (optionally) escrow with Apple is stored in the iCloud Keychain, which is cryptographically secured by HSM-backed, rate-limited protections. You can (and should) watch [VIDEO] for all the details about how iCloud is protected.

Which is a very good thing. iCloud is much more secure than most people realize because most people don’t take the 30 minutes to learn how it is architected. You can (and should) watch [VIDEO] for all the details about how iCloud is protected, but especially the time-linked section. :)