Apple Confirms Unencrypted Kernel in iOS 10 Beta is Intentional

Yesterday it was discovered that iOS 10 does not feature an encrypted kernel, allowing users and researchers access to the core of the operating system and its inner workings. It was unclear at the time whether the lack of encryption was an accident or intentional, but today Apple confirmed to TechCrunch that the company did not encrypt the kernel for a reason.

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“The kernel cache doesn’t contain any user info, and by unencrypting it we’re able to optimize the operating system’s performance without compromising security,” an Apple spokesperson told TechCrunch.

The kernel, which dictates how software can use hardware and keeps the device secure, is unencrypted so that developers and researchers can "poke around" and find potential security flaws. Because the kernel is easier to access and flaws may be easier to find, Apple can more easily and more quickly patch potential issues.

The move is a shift for Apple, who had encrypted the kernel in past versions of iOS, leaving developers and researchers out of the loop on the inner workings of the operating system. As noted by security expert Jonathan Zdziarski, it's likely that Apple has made this shift to prevent groups from "hoarding" vulnerabilities in Apple's software, like the vulnerability used by the FBI to break into the iPhone 5c of the San Bernardino shooter.

Related Forum: iOS 10

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Top Rated Comments

Quu Avatar
120 months ago
I'd just like to point something out. Apple does not offer a bug bounty program. That is to say there is no bounty to be awarded if you report a bug to them no matter how serious it is.

By contrast Microsoft offers $100,000 for a unique kernel level exploit, $15,000 for a Edge browser exploit and $100,000 for a unique solution to a presented exploit that they have yet to come up with / implement.

So if you were to find an Edge browser exploit in Windows 10 and another exploit that allowed you to jump the sandbox and gain root access to the operating system and then figured out a solution to stop the attack that is safe and implementable you could earn yourself $215,000.

Find the same in iOS, macOS, watchOS or tvOS and earn $0. It's about time Apple got serious and offered their own bug bounty program. It's the most meaningful way to get serious vulnerabilities reported.

And remember the FBI and NSA are paying upwards of $1 Million dollars (as shown in congress reports) for root level attacks on iOS, macOS and Windows. That is the competition. If you're a security researcher who're you gonna tell? Apple and earn nothing or the NSA/FBI and change your entire life?
Score: 57 Votes (Like | Disagree)
6836838 Avatar
120 months ago
I see. So open-source now equals openly exposing vulnerabilities for the collective good so a select user group can not exponentially exploit said vulnerability.

Yeah, didn't work too well for Android, though.
You're very confused. Please research the difference between binaries and source code.
Score: 27 Votes (Like | Disagree)
RichTeer Avatar
120 months ago
I see. So open-source now equals openly exposing vulnerabilities for the collective good so a select user group can not exponentially exploit said vulnerability.
Umm, unencrypted binary != open source...
Score: 26 Votes (Like | Disagree)
C DM Avatar
120 months ago
I see. So open-source now equals openly exposing vulnerabilities for the collective good so a select user group can not exponentially exploit said vulnerability.

Yeah, didn't work too well for Android, though.
Where does open-source come from? :confused:
Score: 21 Votes (Like | Disagree)
doelcm82 Avatar
120 months ago
In Apple marketing terms, this is called innovation.
Apple marketing is not calling this anything.

You are calling it innovation, and then snickering at the "Apple marketing" in your mind for calling it innovation.

Well done.
Score: 9 Votes (Like | Disagree)
Nothlit Avatar
120 months ago
So has anyone in the tech press asked them why only the 64-bit kernelcache was left unencrypted while the 32-bit kernelcache remains encrypted? What about the update and restore ramdisks, which also remain encrypted? The rest of the boot chain? Why not let us peek at those, too?

Apple PR's statement that "[t]he kernel cache doesn't contain any user info" is ridiculously obvious to anyone with technical knowledge in this area. That statement is clearly only intended to placate the non-technical masses who might hear "Apple" and "unencrypted" in the same sentence and get worried about the privacy battle.

Secondly, what sort of performance improvement can this possibly make? Even assuming the kernelcache has to be decrypted once per boot, that must take what, a couple hundred milliseconds for the hardware-accelerated AES engine to do its thing?

I am really baffled by Apple's response. If it was indeed intentional, it must have been for reasons other than what they are saying.
Score: 8 Votes (Like | Disagree)