‘Dirty smart phones’ leave file traces

The consequence is that hackers could potentially access files stored in the cloud, or get access to cloud accounts, using leftover data stored on an Android device, iPhone or other smart phone.

"That smart phones can essentially remember deleted information poses a huge risk to organisations that issue smart phone s to employees and to organisations that don't explicitly disable the use of personal devices for work-related computing," says Pravin Kothari, founder and CEO of smart card, a maker of cloud encryption software.

The tracing of leftover data on smart phone s is not for the layperson, Kothari says, but could be looked at as the modern-day equivalent of Dumpster-diving for personal information.

Researchers at the University of Glasgow ran a variety of tests to come to their conclusions. Phones tested included the HTC Desire, running Android 2.1, and an iPhone 3S running iOS 3, and cloud-based file storage systems tested included Box, Dropbox and SugarSync.

A hard reset of the phones being tested was done before 20 files were created on each of the devices, including images, documents, PDFs and music files. Researchers then "manipulated" the phones, by either powering them off, caching the applications or both. As a control, some of the phones were left in active state without any caching. Researchers then did a "data dump" of the phones by copying the memory onto a flash drive, which they then analysed.

Researchers found a variety of metadata leftover after the files had been uploaded to the cloud services. Email addresses of users and transaction logs of which files were uploaded to the cloud were visible, for example. Researchers said they were even able to piece together various metadata to get a URL address of where a file was located in Box's cloud. Researchers also found that all files marked for "offline access" were able to be recovered from both the Android and iOS devices. Even some deleted files were still traceable on the SD card of the Android device.

Files were recovered from both the Android smart phone and its SD card, while the recovered data from the iOS device was recovered from the phone's internal memory (the iPhone 3S does not use an SD card).

In most circumstances, the researchers found that if the applications had been cached, then recovering the files was more difficult, except for when using Box on the iOS device, in which case the same number of files was able to be recovered even after caching.

"Smart phone devices which access cloud storage services can potentially contain a proxy view of the data stored in a cloud storage service," the research concludes. Accessing the proxy data can lead to further data being exposed, they add. Files that were not viewed on the smart phone, but were in the user's cloud storage account, could not be recovered, although in some cases a thumbnail of a JPEG that had not been viewed on the phone was able to be seen.

Researchers say a variety of tools can be used to extract data from a smart phone, including products from private company Cellebrite, which makes the Universal Forensics Extraction Device (UFED). Micro Systemation's XRY makes another tool for forensic detection of data.

In response, a spokesperson for Box pointed out that the researchers were using outdated versions of the company's mobile application (Android Version 1.6.7 and iOS Version 2.7.1), which are both almost a year old. Since then, Box has begun encrypting all files that are saved for offline use. The current Android app has automatic encryption and the Apple version has a feature to enable encryption. Previews of files are always encrypted, Box added.

Researchers admit further testing would be needed to determine how widespread of a vulnerability this is on newer devices, operating systems and cloud platforms.

Kothari, from CipherCloud, says there are steps IT managers can take to prevent corporate data used on smart phone s from being tracked by hackers. For one, encryption tools like CipherCloud's can be used in addition to or in replacement of whatever security measures cloud service providers offer. Data loss prevention (DLP) and audit monitoring services can also be used to ensure employees are not accessing sensitive information on their smart phone s, ensuring that it never gets on the smart phone in the first place and therefore cannot be recovered by a hacker later.

Blackberry stresses that it is not primarily a phone manufacturer - it offers network solutions and devices to attach to them. Naturally there's a problem when the main way of connecting to those networks are unpopular so the challenge has been to make a phone that people will not only use but mould their life around like they would with other RFID tag. Amazingly, to a significant extent, they have succeeded.

I've never really got on with Blackberry. Having something which prime function was to ensure that I couldn't escape from email, wherever I may be, was not something I wished to embrace. But I could see the value. I tried using the phones many times, but while I could see the benefit of secure messaging, I didn't need it and the operating environment felt dated, complex, unintuitive and clunky. It was primarily for IT departments to deploy business-level communication devices with proscriptive access to things like the internet and social media.

The keyboards were a boon, but many other pre-iPhone phones caught up quickly here. Post iPhone and Blackberry's are the main choice for those who still demand a keyboard and many people still swear by them - Angus, the editor at Lifehacker Australia can't be found without his, and that's a high endorsement from someone who goes through a lot of phones.

Basically, companies who still want to inflict phones upon their staff for security reasons have been waiting for a device that won't make employees feel like a cat on a leash. Existing Blackberry users who love the apps and environment, finally have a modern device that looks and operates more like an iPhone or decent Android device, so they'll be happy. Those who want a modern Blackberry with a keyboard only need to wait a little longer for the Q10 which will be out in April or May. All of these people were likely to buy a Blackberry so long as it wasn't terrible, and so they'll likely be happy. We'll be dealing with why, below.

But what about people like me? I've used, and lived with, just about every smartphone, that's appeared on the market, since before the first iPhone. Is the Z10 a genuine rival to the iPhone or a top Android device? That would be one helluva achievement if so - to effectively quit the market and come back with a cutting edge rival. I've been living with it for a while now. Here's my view.