The UDID was a bad idea from the beginning and Apple should have realised its privacy implications, Cortesi said.
The other personal data that accompanied many of the UDIDs was intentionally removed, the hackers said.
However, the leaked UDIDs — random-looking codes made up of letters and numbers that are unique to every iOS device — appear to be authentic.
A check of a random sample of UDIDs using the publicly accessible API (application programming interface) of OpenFeint, a social networking platform for iOS games, revealed that many of them correspond to devices whose owners have OpenFeint player profiles.
Apple had told developers late last year that it planned to block the ability of iOS apps to access the UDID but in order to satisfy lawmakers who have put iOS under scrutiny as part of a wider investigation into how mobile apps impact on individual's privacy this policy appears to have been brought forward.
As Wes Biggs, the co-founder and CTO of mobile advertising firmAdfonicexplained, UDID data is invaluable to developers and mobile advertising firms.
As the iOS application ecosystem has grown in the past three years, UDID has emerged as the de facto way of enabling a host of functions that make developers' lives easier.
How to Install iOS 7 GM Legally via Developer Account or Registered UDID
Steps to Install iOS 7 Beta 5 Legally via Developer Account or Registered UDID
VP at Komli Mobile, Amit Bhartiya, stated, "Following the launch of iPhone 5, we have adapted our SDK to track the IFA in addition to UDIDs
Steps to install iOS 7 Beta 4 without UDID
or developer account
Of course this is just one theory, and there are several others being postulated since the leaked Apple UDIDs
were posted online.