Intrepidus Group

Tracking Down the UDID Breach Source

Posted: September 10, 2012 – 12:00 pm | Author: | Filed under: Breach, iOS, Mobile Security, Privacy

I’d heard about the alleged FBI/Apple UDID leak shortly after arriving at work last Tuesday morning, and immediately downloaded and began reviewing the data. Less than an hour later, I’d surmised that comparing apps across multiple devices might help narrow down the source.

Several hours later, at 3:00, I saw a tweet from @Jack_Daniel suggesting that people checking their UDIDs in online forms only enter partial numbers . And that made me wonder: “How many digits is the minimum people need to enter in order to be guaranteed a unique result?” Sort to the rescue:

cat data | cut -c 2-7 | sort | uniq -c | more

This gave me a bunch of repeats. That’s not too surprising, as I’m only looking at 6 digits. Next up was 8 digits, and still I saw hundreds of repeats. Then I changed tactics and simply counted the number of unique UDIDs…and I came up with a number significantly different from the 1,000,001 that were released: 985,117. So there are almost 15,000 duplicates. Looking further, I saw that many of these duplicates have different device tokens, prompting a tweet, about 3:15:

Interesting. Just noticed there are UDID duplicates in that 
data dump, with multiple APNS tokens. Different app providers, 
or multiple regs?

About 45 minutes later, on my way home, @danimal suggested: “@DarthNull multiple apps? Seems like maybe a game or ad company.” I immediately thought, damn, that must be it. At 4:23 pm, I replied “Yes! makes sense.”

And two minutes after that, I found what seemed to be the source of the breach.

I had decided to look more closely at the most frequently repeated device IDs, on the theory that perhaps that would belong to a developer. They’d naturally test multiple apps for their company, each of which should have a different device token. So first, more shell magic:

cat data | cut -c 2-7 | sort | uniq -c | sort -n -r | head

Wow, some are repeated 10 or even 11 times!

  11 4daa64abd
  10 d1f575954
  10 aa5c7aedb
   8 12e6ec97e
   7 f661c1396
   7 4225e2a59
   6 91a83b0e3
   6 480074431

I searched for the first one, and found 11 different entries for a “Gary Miller.” Nothing much there. The next one, though, had some interesting device names:

'Bluetoad Support'
'Bluetoad Support'
'BT iPad WiFi'
'BT iPad WiFi'
'CSR iPad'
'Customer Service iPad'
'Developer iPad'
'Developer iPad'
'Hutch Hicken’s iPad'
'Hutch Hicken’s iPad'

Six different names, four repeated twice (implying at least a pair of apps and several users). Then I looked at the next entry, with 10 repeats: it’s variously named Robert, Red, and HP Pavilion. Meh. The entry, with 8 repeats: GoldPad. But the entry with 7 repeats really grabbed my attention:

'Bluetoad iPad'
'Bluetoad iPad'
'Client iPad BT'
'Client iPad BT'
'CSR/Marketing iPad'
'CSR/Marketing iPad'
'Jessica Aslanian’s iPad'

Support? Customer service? Developer? Marketing? A quick Google search revealed that, yes, BlueToad does develop iOS apps. In fact, they build magazine apps for many different publishers, and a quick trip through the iTunes store showed me that these applications use Push Notifications.

As this was the kids’ first day of school, we went out for a nice dinner to celebrate. While there, I thought more about what I’d found, and decided to roll the dice: I sent an email to BlueToad, using the email address on their website. I didn’t say much, just that there’d been a breach involving UDID and push tokens, and I’ve found some interesting data that suggest they may be involved. After returning home, I spent another four hours digging for more.

By the time I went to bed, I had identified nineteen different devices, each tied to BlueToad in some way. One, appearing four times, is twice named “Hutch” (their CIO), and twice named “Paul’s gift to Brad” (Paul being the first name of the CEO, and Brad being their Chief Creative Officer). I found iPhones and iPads belonging to their CEO, CIO, CCO, a customer service rep, the Director of Digital Services, the lead System Admin, and a Senior Developer.

This felt really significant. But as I started writing up my notes, doubt crept in. What are some other explanations? Perhaps everyone at the company uses a common suite of applications. Like the same timesheet app, for example. Then of course they’d all appear in the data. But even still, I couldn’t shake the feeling that I’m onto something.

I spent much of the next day writing a detailed analysis of the situation for our blog. Then, about 4:30, I drafted a follow-up message to BlueToad about what I’ve found, how I found it, and what I think it means. Also, I mentioned that though I’m reluctant to publicly name them without more solid data, it seems likely that others will also find their name in the dump.

Since I now have several more employee’s names, I spent some time looking for email addresses, to (hopefully) increase the chance of a response. While searching, I stumbled on a partial password dump for the company! And it was dated March 14, the same week that the hackers claimed they’d hacked into the FBI computer. Suddenly, I felt a lot more confident again, and I mentioned this connection in the email.

Shortly after 8:00 that evening, I heard from Hutch Hicken, their CIO. He thanked me for what I’ve done, and for my discretion in contacting them first rather than simply going public. He told me that they’re assessing the situation, but don’t yet know anything for certain. He didn’t think the March leak (which they’d already been aware of) was related, but that the rest of my findings were concerning. He told me they plan to “do this right,” he promised to keep me in the loop (as much as is feasible for a non-employee).

Most of the next day (Thursday), I didn’t really hear much. Then about 2:30 on Friday, Hutch called me again. Almost immediately, he told me that we can talk, but only if I agree to embargo the story until noon on Monday. My response was “Well, the fact that you’re asking me this tells me that I’ll want to say yes,” so naturally I agree.

I’m told that they’re confident the leak came from them, and he filled me in on some of the technical details (I’ll leave those details to others, to make sure I don’t make any mistakes). But they’re almost certain of their involvement, and are continuing to handle the situation.

Then he hit me with a big surprise: Kerry Sanders, a correspondent for NBC Nightly news in Miami, wants to interview me. On camera. He’s in the next room, and the phone gets passed to the reporter, and next thing I know we’re arranging an interview that night. He didn’t arrive at my house until 11:00 (his plane was delayed), and we spent 45 minutes talking about what I found, how I found it, the privacy implications of the breach, and other related topics.

By the time he left at midnight, I was exhausted. As I write this, I still don’t know how much of the interview he’s going to use, or even if it’s going to make it onto the air Monday night. Either way, it was certainly a surreal way to conclude what started out largely as another puzzle hunt.

I’m still not completely clear on all the technical details. Was BlueToad really the source of the breach? How did the data get to the FBI (if it really did at all)? Or is it possible this is just a secondary breach, not even related to the UDID leak, and it was just a coincidence that I noticed? Finally, why haven’t I noticed any of their applications in the (very few) lists of apps I’ve received?

Hopefully, I’ll learn the answers to many of these questions in the coming days. Either way, I’m glad to have been able to help, and offer my thanks to BlueToad for their cooperation, and their quick response.

UPDATE: Here’s the link for the NBC Nightly News post.

UPDATE: Timo Hetzel kindly corrected a misunderstanding that I had regarding how device tokens are created. I had believed that each application on a device had a different token, but that was in error — it’s a single device token for all apps on a device. So whenever I saw many tokens for a given device, that represented (in most cases) multiple refreshes of the same device. However, apps using the development “sandbox” Push Server receive a different token than what apps using the main production server receive, so seeing multiple devices from BlueToad, each with exactly two tokens for a given device name, further implicates the use of those devices by developers.

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  1. Mek0s
    Posted September 10, 2012 at 12:32 pm | Permalink

    GJ on this guys’. Much respect.

  2. Posted September 10, 2012 at 1:11 pm | Permalink

    nice work!

  3. mattjay
    Posted September 10, 2012 at 1:24 pm | Permalink

    Really great to see less echo chamber finger pointing and actual research. Great job!

  4. Posted September 10, 2012 at 2:14 pm | Permalink

    Nice work Mr. Schuetz! I admit that I had started to look for patterns in the names (why do so many Dawn’s own iOS devices?) but you nailed it. Congrats on some inspired analysis!

  5. ohgoodnesswhat
    Posted September 10, 2012 at 3:03 pm | Permalink


    And how much was BlueToad paid to be the alibi?

  6. Randy
    Posted September 10, 2012 at 3:23 pm | Permalink

    Well done, both technically, ethically, and professionally.

  7. Posted September 10, 2012 at 9:09 pm | Permalink

    I’m still skeptical about the company’s claims. Of course, I don’t have the technical details they shared with you.

    However, initially their statement said a “significant match” and then it was escalated to “100% certainty”, etc.

    Can we rule out the possibility that their UIDs were added to some other set of UIDs from elsewhere and acquired by the FBI and subsequently by the hackers? I think not.

    I think we can completely rule out the possibility that the FBI is not lying, just on general principle. If you know who Sibel Edmonds is, you know the FBI simply cannot be trusted. Period.

    However, at this point, clearly the hackers involved need to provide more evidence of the source of the file and proof that they indeed have more data as well as the user names, in order to bolster their case. If they can do that, then Blue Toad is only one of the sources of that data and the FBI is still on the hook.

  8. Katie
    Posted September 10, 2012 at 10:00 pm | Permalink

    DarthNull you rock!

  9. Posted September 10, 2012 at 10:44 pm | Permalink

    Nice work! Fun reading through your detective work.

  10. afc
    Posted September 10, 2012 at 11:05 pm | Permalink

    Props to you for your curiosity. Great interview BTW.

  11. Posted September 10, 2012 at 11:05 pm | Permalink

    You rock David!

  12. Podesta
    Posted September 10, 2012 at 11:45 pm | Permalink

    I would like to know what apps Bluetoad publishes. That’s the easiest way for a non-techy to determine whether he or she is a victim of the breach.

  13. mcgorgomagan
    Posted September 11, 2012 at 12:53 am | Permalink

    Wait, so everything the FBI ever says is false? Doesn’t that make them exactly as reliable as if everything they said was true? What makes them unreliable as a source is if you can’t *tell* if they’re lying.

  14. Scruff
    Posted September 11, 2012 at 3:34 am | Permalink

    Your evidence? Otherwise your comment is worth nothing, and adds exactly zero to the public knowledge.

    Cough up your evidence, or shut the hell up.

  15. Nik
    Posted September 11, 2012 at 3:41 am | Permalink

    Now we just need an explanation of why it was reported as being data on an FBI laptop – for the lulz, to harm Apple, to sound uber hacker ?

  16. Saram
    Posted September 11, 2012 at 3:51 am | Permalink

    Wow!!! Good Work….

  17. Posted September 11, 2012 at 5:07 am | Permalink

    Thanks for this, it’s a solid analysis. It hadn’t occurred to me to do a frequency analysis on the UDID strings themselves, I was more concerned with the Device Name field,…. Although it does support my analysis, BlueToad makes apps for magazine publishers, hence the predominance of of the iPad over the iPhone in my results. Also they seem to mostly market into the U.S., which supports the ethnicity findings. I can’t find a list of what titles they technology underpins, but I’m fairly confident you’ll find they are magazines targeted at men in their 30′s and 40′s. I’d actually been really confused about what type of app could possibly have that narrow a demographic, and this sort of clears up my confusion. Nice!

  18. jasontoheal
    Posted September 11, 2012 at 6:20 am | Permalink

    good stuff.

  19. Saram
    Posted September 11, 2012 at 7:11 am | Permalink

    How did track the UDID to device name

  20. SomeGuy
    Posted September 11, 2012 at 8:31 am | Permalink

    Yes. Maybe. Yes

  21. Jim Ellison
    Posted September 11, 2012 at 9:05 am | Permalink

    Your sleuthing reminds me of “The Cuckoo’s Egg” by Clifford Stoll who hunted down a hacker because of an anomaly between 2 account balances in a Unix system.

  22. crush
    Posted September 11, 2012 at 10:50 am | Permalink

    so now off to find the other dump “partial password dump” and yes you would think that they would of put more info from the pc to prove it was the fbi’s. if you time to dump a file you of grabbed the the hashdumps from the pc at least i would think anyway

  23. LEDiogenes
    Posted September 11, 2012 at 10:54 am | Permalink

    Ding Ding. And Scruff the sock puppet comes along to quickly squash those who read between the lines.

  24. Bill
    Posted September 11, 2012 at 11:07 am | Permalink

    Question- I looked up a specific UUID and it linked to “RamSOFT”, searching this is looks like its a physician technology company. So my question is if the device was “supposedly” brand new, and this UUID is linked somewhere to that name, do you think APPLE is providing previously owned tablets to people….Or am I just way off..

  25. Posted September 11, 2012 at 11:09 am | Permalink

    Nice work. I love how you used nothing more than cut, sort, uniq, and cat to crack the puzzle.

  26. Augustus
    Posted September 11, 2012 at 11:11 am | Permalink


  27. John
    Posted September 11, 2012 at 2:40 pm | Permalink

    I’m just curious as to why Bluetoad CIO had Kerry Sanders from NBC in the next room for an interview? Also curious as to how Kerry Sanders knew about the breach if bluetoad had only been discussing it with the author? Theory – Maybe the leak was done on purpose to convince the public that tighter regulations are needed for the internet so the govt can impose greater restrictions on the general population in the name of “security” or “commerce”. Would anybody have paid attention if it were RIM user data being leaked? Google or Apple are the only two worth following so why no go with apple. Makes for sexy news, dont you think?


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