Pierluigi Paganini July 22, 2014

Apple has worked hard to make iOS devices reasonably secure but hidden services could be exploited to steal every user’s data in a stealthy way.

Have you tried to enumerate the functionalities and services in your Apple iOS?

You’d be surprised to find that numerous hidden features and services are not documented, some of them could be abused to bypass security functionalities like the backup encryption on iOS devices.

These functionalities could represent a serious threat to users’ privacy and could be exploited by hackers to access large amounts of users’ personal data. The researcher Jonathan Zdziarski has conducted different studies on the architecture of iOS discovering that different services are unnecessary for users and could be used to bypass security defenses.  Zdziarski is a prolific expert, he designed many of the initial methods for acquiring forensic data from Apple iOS mobile devices.

Zdziarski presented his discoveries in a speech at the HOPE X conference, the scientist highlighted the presence of the mobile file_relay (com.apple.mobile.file_relay) services on iOS that can be accessed remotely or via USB to bypass the backup encryption, exploiting the feature an attacker can access all of the data encrypted via the data protection if the device has not been rebooted since the last time the user entered the PIN.

The file_relay tool can be used to steal user’s information from iOS device, including email, location, social media accounts, the address book and the user cache folder, below the description provided in the presentation:

• Accounts A list of email, Twitter, iCloud, Facebook etc. accounts configured on the device.
• AddressBook A copy of the user’s address book SQLite database; deleted records recoverable.
• Caches The user cache folder: suspend screenshots (last thing you were looking at), shared images, offline content, clipboard/pasteboard, map tile images, keyboard typing cache, other personal data.

“Between this tool and other services, you can get almost the same information you could get from a complete backup,” “What concerns me the most is that this all bypasses the consumer backup encryption. When you click that button to encrypt the backup, Apple has made a promise that the data that comes off the device will be encrypted.” Zdziarski said in an interview. 

Zdziarski explained that different hidden services that bypass the encrypted backup protection don’t require the use of developer mode, he also confirmed the presence on the mobile iOS of a packet capture tool which could be used to dump all of the inbound and outbound HTTP data and runs in stealthy mode.

The expert also mentioned a component of the file_relay service called HFSMeta that is implemented in iOS 7 and can create a complete metadata image of the device’s file system, the information includes metadata on all files and all installed apps.

“Some of this data shouldn’t be on the phone. HFSMeta creates a disk image of everything that’s on the phone, not the content but the metadata,”“There’s not even an engineering use for that.”  Zdziarski explained. 

The fact that Apple iOS includes such functionalities is not surprising, in one of the document leaked by Edward Snowden it is described  DROPOUTJEEP as a spyware developed by ANT (Advanced or Access Network Technology) division of the NSA that is used to gain backdoor access to the mobile.

Zdziarski clarified that his study hasn’t the purpose to demonstrate that the above features were designed for surveillance purposes, but he believes that Intelligence agencies are exploiting them.

“I’m not saying at all that Apple is working with the NSA,” he said. “But at the very least, there’s a very strong case to say that the NSA knows about and exploits these capabilities.”

Give a look to the slides of the presentation … their are a mine of interesting information.

Pierluigi Paganini

Security Affairs –  (iOs, hidden services)