The FBI on Tuesday denied that the 1 million unique device identifiers for Apple devices (UDIDs) posted publicly by hacker group AntiSec on Monday had come from its computers.
In a brief statement, the FBI's national press office said the agency was aware of reports that an FBI laptop had been compromised and that private data regarding Apple's UDIDs had been exposed. "At this time, there is no evidence indicating that an FBI laptop was compromised or that the FBI either sought or obtained this data," the agency said.
The FBI's denial comes less than a day after AntiSec, a splinter group of hacking collective Anonymous, announced on Pastebin that it had accessed more than 12 million Apple UDIDs from the computer of FBI special agent Christopher Stangl of the agency's Regional Cyber Action Team in New York.
The hacker group claimed that the information it accessed from the FBI agent's computer included UDID user names, names of devices, types of devices, Apple Push Notification Service tokens, zip codes, cell phone numbers and addresses.
AntiSec's announcement prompted speculation over why the FBI might have collected the information and what it might have been tracking. Many media reports were quick to note that Stangl had been the star of an FBI promotional video about three years ago in which the agency asked hackers for their help in fighting cybercrime.
Apple's UDIDs are a set of alphanumeric characters used to uniquely identify an iPhone or iPad. The numbers are designed to let application developers track how many users have downloaded their applications and to gather other information for data analytics. Application developers have used the UDIDs to collect personal information about the device owner, including name, age, gender, device location and phone numbers.
Apple earlier this year announced that new iOS applications would not be permitted to track UDIDs in an apparent response to privacy concerns raised over the tracking.
In its Pastebin message, AntiSec said that it had decided to post the information to expose the FBI's secret collection and tracking of Apple UDIDs. "FBI will, as usual, deny or ignore this uncomfortable thingie and everybody will forget the whole thing at amazing speed," the group said in its post.
The FBI's quick denial of the alleged breach comes even as some have begun looking elsewhere for the source of the leaked data. In a blog post, Marco Arment, a technology blogger based in New York, wrote Tuesday that a look at the data leaked by AntiSec suggests that it may have come from an application developer.
"All of this information could have been collected from an app transmitting data to a server," Arment wrote in his blog. "For instance, this is exactly the information that an ad network would want to collect. And in order to get stats from 12 million devices, it would probably need to be from a set of popular, free apps... where you'd probably see ads."
He pointed to a free identity theft protection application called AllClearID as a likely source of the data based on the name of the file containing the UDIDs that AntiSec said it had accessed from the FBI computer.
A spokeswoman for AllClear ID however denied Tuesday that it had been the source of the data leak and said the blogger had jumped to the wrong conclusion. "To clarify, AllClear ID does not collect, nor has it ever collected, UDIDs. This incident is not linked to AllClear ID."
Jaikumar Vijayan covers data security and privacy issues, financial services security and e-voting for Computerworld. Follow Jaikumar on Twitter at @jaivijayan or subscribe to Jaikumar's RSS feed . His e-mail address is firstname.lastname@example.org.