iOS diagnostic services, their uses and protections, outlined by Apple in response to 'backdoor' allegations

Earlier this week Apple reaffirmed to iMore that it had never worked with any government agency to create a backdoor in any product or service. That was in answer to questions raised by Jonathan Zdziarski concerning iOS privacy and security. Apple has now published a new support page titled iOS: About diagnostic capabilities which elaborates on the services Zdziarski called out as data leaks. It does not, however, address vulnerabilities in passcode, pairing keys, or trusted device, though Apple typically does not address those types of things until they've pushed out patches. Here's Apple's full support article on the services:

iOS offers the following diagnostic capabilities to help enterprise IT departments, developers, and AppleCare troubleshoot issues.

Each of these diagnostic capabilities requires the user to have unlocked their device and agreed to trust another computer. Any data transmitted between the iOS device and trusted computer is encrypted with keys not shared with Apple. For users who have enabled iTunes Wi-Fi Sync on a trusted computer, these services may also be accessed wirelessly by that computer.


pcapd supports diagnostic packet capture from an iOS device to a trusted computer. This is useful for troubleshooting and diagnosing issues with apps on the device as well as enterprise VPN connections. You can find more information at


file_relay supports limited copying of diagnostic data from a device. This service is separate from user-generated backups, does not have access to all data on the device, and respects iOS Data Protection. Apple engineering uses file_relay on internal devices to qualify customer configurations. AppleCare, with user consent, can also use this tool to gather relevant diagnostic data from users' devices.


house_arrest is used by iTunes to transfer documents to and from an iOS device for apps that support this functionality. This is also used by Xcode to assist in the transfer of test data to a device while an app is in development.

When Chinese TV called iOS a location tracker, Apple responded on the consumer facing portion of their Chinese website, and in much more direct-to-customer terms. It's interesting to see Apple address the specific services in Zdziarski claims, but to address them in a support document, and to address them in technical terms.

Apple is already increasing the security in iOS 8. Hopefully diagnostics, pairing records, and any other newly discovered vectors will have their security increased as well, and soon.

Source: Apple Support (opens in new tab)

Rene Ritchie

Rene Ritchie is one of the most respected Apple analysts in the business, reaching a combined audience of over 40 million readers a month. His YouTube channel, Vector, has over 90 thousand subscribers and 14 million views and his podcasts, including Debug, have been downloaded over 20 million times. He also regularly co-hosts MacBreak Weekly for the TWiT network and co-hosted CES Live! and Talk Mobile. Based in Montreal, Rene is a former director of product marketing, web developer, and graphic designer. He's authored several books and appeared on numerous television and radio segments to discuss Apple and the technology industry. When not working, he likes to cook, grapple, and spend time with his friends and family.

  • The original presentation outlined what data was available from these services, including items like messages and camera roll data. What is conspicuously absent in this response is a list of what "limited diagnostic data" entails, much less a denial that those personal types of data are exposed. Lacking those details, this is a pretty weak response.
  • If you go to the link Apple provided (, that link states the following: "iOS does not support packet tracing directly.", yet this undocumented backdoor is made for packet traces within iOS. Go figure. The other explanations are equally as silly and all Apple is doing is digging a deeper hole. Apple PR needs help.
  • Seriously? Please try to interpret it they way those kb docs are written. "Directly" in this context means "straight on the device without any additional device/computer"
    If you still think they messed that document up, let's dig deeper;)
  • How do you explain the very next line? "If you connect your iOS device to a Mac via USB, you can use an OS X packet trace program to gather and analyze traces using the remote virtual interface feature". To be fair, that link was last updated on 10/2013 and Apple was caught with undocumented backdoors.
  • Yeah, that's not directly. You need to use a separate device (eg. a mac), you need to _enter your passcode_ and _trust_ that computer for this to work. In my read, that's far away from being a backdoor.
  • Apple are spooked. With good reason.
    They are doing the same as every other big company, and that is get away with whatever they can while hiding as much as possible and only speaking publicly, (in a kind of Donald Rumsfeld way), about what they were caught with. I don’t condone this behaviour but I certainly expect it. They should have put out a much more substantial rebut. (Have a look at the response from Zdziarski).
  • apple is full of shit. such a huge company which gets so much tax break from the government doesnt work with any government agency, yea ok. at least google tellls us what they are doing, apple is sneaky. All tech companies do it, apple is just a hypocrite acting as if they are different
  • I think it is like before with the original set of leaks from snowden where they "couldn't say", I don't really trust any of these companies, if the government/NSA says bend over they will, its not their fault they have so much power that they can just take any data they want ala carte.