iPhones secretly track 'scary amount' of your movements
Your location down to the second, researchers say
Apple's iPhone and iPad constantly track users' physical location and store the data in unencrypted files that can be read by anyone with physical access to the device, computer researchers said.
The file, which is stored on both the iOS device and any computers that store backups of its data, can be used to reconstruct a detailed snapshot of the user's comings and goings, down to the second, the researchers, Pete Warden and Alasdair Allen, blogged. The revelation, which Apple has never acknowledged, means iPhones and iPads put their users at considerable risk from snoops.
“The most immediate problem is that this data is stored in an easily-readable form on your machine,” they wrote. “Any other program you run or user with access to your machine can look through it. By passively logging your location without your permission, Apple have made it possible for anyone from a jealous spouse to a private investigator to get a detailed picture of your movements.”
Apple representatives didn't respond to emails and phones calls from The Register seeking comment.
The researchers were quick to point out that there is no evidence Apple or anyone else has accessed the information. They didn't offer any guidance on how to turn off the movement tracker, but suggested users encrypt backups when syncing devices with iTunes to prevent the data from being read by people who have access to the underlying computer.
But that advice would do nothing to deter those who steal or otherwise obtain an iPhone or iPad.
The data is stored in the /Library/Application Support/MobileSync/Backups/ folder of computers that sync to the iDevice. While most of the folders and files inside contain pseudo-random names, it's possible to unscramble them by examining files called Manifest.mbdb and Manifest.mbdx. With a few more steps, users will extract a database in the SQLite format that's easily read with multiple applications.
The researchers said that locations are tracked by triangulating near-by cellphone towers. That suggests that the movements are tracked even when an iDevice's GPS features are turned off.
“I looked at the file on my phone and it had tons and tons of entries,” said Miller, who is a principal security analyst at Independent Security Evaluators. “They were all places I've been. For me, at least, it had lots of information.”
The researchers have released open-source software that makes the entire process a snap. It also plots the information to a map that shows the movements of the user. While the locations are stored down to the second, the researchers said, their software intentionally reduces the time to weekly increments to make the data less useful to snoops.
The researchers said they also diminished the location granularity, but they pointed out that prosecutors, private investigators and others who reproduce their work are under no such constraints.
The researchers said they stumbled on the database while working on several location data visualization projects.
“At first we weren't sure how much data was there, but after we dug further and visualized the extracted data, it became clear that there was a scary amount of detail on our movements,” they wrote. “It also became obvious that at least some other people knew about it, but it wasn't being publicized.”
Their post doesn't elaborate on who these other people may be, and the researchers didn't respond to email seeking an interview. This article will be updated if we hear back from either them or Apple. ®
Forensics investigator Christoper Vance alluded to the iDevice location tracking as long ago as September in his Cellular.Sherlock blog. “This fun little database is stuffed FULL of GPS data ripe for the picking,” he warned of the SQLite file, which is titled consolidated.db. In an update, he said that in addition to a CellLocation table, the database contains a WifiLocation table.
What's more, Freedom to Tinker blogger Will Clarkson said he dumped the database contents on a two-month-old CDMA iPhone and found more than 53,000 distinct MAC addresses stored in the WifiLocation table, “suggesting that this data is stored not just for networks your device connects to but for every network your phone was aware of (i.e. the network at the Starbucks you walked by -- but didn’t connect to).”
This article was updated to add comments from Charlie Miller.