Forensic snoops: It doesn't take a Genius to break into an iPhone

Analysis Forensic tools against smartphones allow basic 4-digit phone passcodes to be bypassed in minutes.

However, more complex passcodes are far more difficult to defeat and might even leave some information of seized Androids or iPhones outside the range of many tools, according to computer forensics experts.

A YouTube video – which has since been pulled – that accompanied a recent article by Forbes explained how Swedish firm Micro Systemation’s XRY tool enabled law enforcement official to bypass an iPhone passcode and gain access to call records, location data, photos and other information in a matter of minutes.

The process is akin to jailbreaking and relies on exploiting vulnerabilities on the device itself, rather than entering through any backdoor. Once a device is jailbroken, the XRY utility is installed and used to brute-force a passcode.

Once a passcode is obtained it then becomes a simple matter to extract sensitive information – including call logs, messages, web browsing history and other data – from a handset. XRY dumps this data on a Windows PC and provides a user interface that allows data to be easily explored.

Current generations of Micro Systemation’s XRY tool only work on the iPhone 4 or iPad and earlier. The firm also markets tools to extract the same sort of information from android smartphone, Blackberries, Windows Mobile phones or other devices. The firm sells to law enforcement, military and government clients.

The Micro Systemation video went viral after the Forbes article prompting the firm to remove it from YouTube.

Mike Dickinson, Micro Systemation’s marketing director, explained that his clients didn't want the capabilities of the technology to be common knowledge. While declining to talk too much about the capabilities of XRY, Dickinson was open to talk more generally about the market for mobile forensics technology, which he described as "booming".

Micro Systemation differentiates itself by specialising in this market and employing more than 30 developers and reverse engineers to research mobile operating system vulnerabilities that its forensic tools might subsequently be able to exploit. While the same forensic tools and techniques can be applied to extract data from a Windows XP machine irrespective of manufacturer and using tools such as EnCase from Guidance Software this does not apply in the mobile smartphone arena. The same approach can be applied to forensically extract data from a Samsung or Sony machine running Vista but not a HTC and Samsung smartphone - even if they were running the same version of Android - Dickinson explains.

"There's a broad range of different ways to embed the technology even before you consider phones from China," Dickinson told El Reg. Dickinson estimated that its customers could expect to come into contact with 3,000 different smartphones and feature phones. Although standardisation means that phones can increasingly be grouped together and attacked in the same way an added completion is becoming more important.

"The next generation of phones store data using hundreds of different apps," Dickinson explained. "Not all this data is stored in the cloud. Handsets retain traces of data but getting at this information requires the development of expertise," he concluded.

Four digit passcode is the default setting on iPhones but users can set a longer 5+ digit passcode or use characters.

Simon Steggles, a director of UK-based computer forensics and data recovery firm Disklabs, said that longer passcodes for devices are far tougher to crack using existing tools, a point Dickinson also conceded in his interview with Forbes.

Disklabs uses technology from Cellebrite that offers similar capabilities to that offered by Micro Systemation’s XRY tool.

Parmjit Bilkhu, one of Disklabs' iPhone experts, explained that Cellebrite, could get past four-digit passcodes in between five and 15 mins, but the new software on MSAB's kit (called  .XRY and .XACT) claims to do it faster. Four-digit passcodes don't present too great an obstacle for the latest mobile forensics tools but longer passcodes are far more of a challenge.

"In the last two months, we have had two iPhones with the advanced passcode on them," Steggles explained. "We were able to obtain a physical read (with Cellebrite, not tested with XRY) and retrieve data (for example call logs, text messages etc). However, we were unable to verify the data as the software does not crack the complex passcode."

"It would be possible to recover additional files if the complex passcode was known," he added.

Smartphones are often seized by law enforcement in multiple types of cases, by no means limited to those connected with any form of computer crime. Sometimes suspects try to destroy evidence on smartphones or tablets after the fact by applying a remote wipe. however Disklabs has developed a countermeasure to this by developing a range of Faraday Bags that investigators can seal seized electronic devices in at the time arrests are made, thwarting subsequent attempt to destroy evidence as well as preserving the state of a smartphone or other device at the time it was seized. ®