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New Way To Crack Secure Bluetooth Devices
moon_monkey writes "Cryptographers have discovered a way to hack Bluetooth-enabled devices even when security features are switched on, according to a report from New Scientist.com. The discovery may make it even easier for hackers to eavesdrop on conversations and charge their own calls to someone else's cellphone. From the article: 'Our attack makes it possible to crack every communication between two Bluetooth devices, and not only if it is the first communication between those devices,'"
where are these cryptographers and their code ?
and why isnt this mentioned on Butraq or Full Disclosure ?
"Too many people are thinking of security instead of opportunity. They seem more afraid of life than death. -- James F. Byrnes"
:)
At bottom of Slashdot screen
See my journal for slashdot ID's by year. Mine created in 2005. http://slashdot.org/journal/289875/slashdot-ids-by-year
If it's a manual step, then it'll require education of the users to not pair their phones in public.
John
Seems like they're keeping their hack top secret..is there anywhere we can find it out? *grins at prospect of free phonecalls*
this fucking depressing, can firmware updates fix these streams of bluetooth hacks? Or is the problem so close to the hardware that nothing but scrapping the device and building from ground-up fix it ?
He is a really nice and very intelligent person, but had a really nasty habit of picking his nose and eating the booger at meetings. This really grossed people out, but still quite a nice person to work with.
Time for WUSB...
Why doesn't the telecom industry learn ?
Guys, what about hiring ONE competent cryptographer to design a wireless protocols ?
While the last dowzin times I've paired devices HAVE been on the bus. I've noticed the auto generating pins are now 5 to 8 digits long.
Further, it's extremely rare that I even SEE Another bluetooth device on the bos or train. While the phones may be popular, not a whole lotta people are using bluetooth, it seems.
Additionally, the phones I've got default to a Bluetooth radio-off mode...ya can't see them unless you a) turn them on (v600) or b) are already paired (nokia 9820)
Lastly, at 15 feet, there's not a large number of people around you that can pull this off (except that poindexter across the aisle with the laptop and dish antenna pointed at you)
Now, if you're being shadowed at less than 20 feet by a guy with a BT headset, get worried...or turn off your phone...or ignore it, you've got a blue bajillion minutes anyway.
"Draco dormiens nunquam titillandus."
Cracking the Bluetooth PIN
This paper describes the implementation of an attack on the Bluetooth security mechanism. Specifically, we describe a passive attack, in which an attacker can find the PIN used during the pairing process. We then describe the cracking speed we can achieve through three optimizations methods. Our fastest optimization employs an algebraic representation of a central cryptographic primitive (SAFER+) used in Bluetooth. Our results show that a 4-digit PIN can be cracked in less than 0.3 sec on an old Pentium III 450MHz computer, and in 0.06 sec on a Pentium IV 3Ghz HT computer.
--AS
Them's the breaks of using a wireless medium. Anyone can participate without jacking-on.
Score +10 pseudo insightful!
...an excuse for my "adult" calls on my phone bills.
__free funny videos
I'm not even surprised.
Then not only didn't you RTFA, but apparently you haven't used Bluetooth, either. Bluetooth is an extremely useful mechanism for many of us. It lets my PDA get on line; and when I hop in my vehicle, my car stereo magically becomes my car phone whenever it rings.
I just wish more devices were Bluetooth enabled (and that this security hole didn't exist.) As is, I'm not losing sleep over this as I don't have a public-transit commute (the sort of place where breaks seem most likely to happen.)
John
The more important issue here is bluetooth keyboards. Can people use this hack to get my password that I'm typing on a wireless keyboard. (Distance issues aside.)
The article doesn't seem to say.
That is an extremely serious flaw. The device sends its key to anyone claiming to forgot theirs? That is a great design. Why wouldn't it only resend the key if it recognized the ID as something it already paired with?
It's like your online bank site giving someone else your password, just because they said they forgot it.
While I doubt this is a widespread serious issue with the small number of bluetooth devices now, it could be an issue on something like a train, where there are a lot of business commuters with both bluetooth gadgets and laptops.
/. ++
Reading between the lines, it seems that the short nature of the PIN code is a key to the exploit. The attacker forces a re-pairing, listens to the re-pairing exchange, and then tries all possible PIN codes to determine which one is the right one. Because a 4-digit PIN has only 10,000 possibilities, it's easy to brute force it.
A longer alphanumeric PIN might be a first step to making this exploit much less practical -- increasing the PIN search time from a fraction of a second to hours or days.
This looks like another classic example of the fundemental tradeoff between usability and security.
Two wrongs don't make a right, but three lefts do.
woohoo! finally a nerd got laid ;)
Bluetooth is also useful for multiple computers. I've paired my laptop and workstation, so I can send a file between them with a single command- no login/disconnect process, no navigation, just completely ad-hoc click and go. The only limitation is that it tops out around 30K/sec, so it can't be used with really large files.
Ok, before this the attacker could only attack when the target link was forming.
With this, you can force them to re-form at will.
Even so, you still need to bruteforce the PIN. The "PIN" is really a 16-byte field, and is not really limited to numeric (or even alphanumeric) characters.
So what can be done:
1) Start using long PIN codes (if your device is limited to numbers, at least use the maximum length)
2) Software update that notifies user of the "forced re-pairing"
3) Allow users to use PIN's beyond the numeric space or possibility to use some pre-shared secret keys.
This affects those of you who use "1234" or similar keys for pairing process for convenience.
To whom it may concern:
How To Crack WEP - Part 1: Setup & Network Recon
and
How To Crack WEP - Part 2: Performing the Crack
Are 2 more interesting cracking articles I came across lately.
...add one of these bad boys and shake vigorously.
Mmm... phreaky...
That green slime had it coming.
That's the combination to my luggage!
XML is like violence. If it doesn't solve the problem, use more.
My guess would be... "Easy money baby."
Wait til you see this new bumper sticker on your daily commute:
"If you can read this, I'm hacking your Bluetooth"
He must be a relative to the Whitehouse family in Cryptonomicon and The Baroque Trilogy - everyone in that family was supposed to be a hacker, after all.
I wonder how long it would take with Pentium 4 disabled.
Free MacMini
Curse goodness when you forget use it...
He was an old man in the 1940's.
How old are you?
Time to get more Paris Hilton pics!
phone in my comment. But ... somehow ... my cell phone appears to be busy.
Ok, so I went and look at my bluetooth devices again (a Motorola cell phone and a Logitech keyboard/mouse) - in both cases, I don't see how this crack would actually work:
- With the Logitech keyboard, you actually have to type in the PIN from the keyboard in order for it to pair.
- The motorola must be told to pair specifically - so if it loses connection with a device, it won't automatically re-pair because I haven't made my phone pairable. To make the phone pairable requires a specific menu sequence and then it's only valid for about 30 seconds (and shuts off again).
In both these cases, I don't see a hacker getting in even with spoofing, because both of those events require user intervention (so perhaps the dumb user won't understand...)
I tried one more thing to confirm this - I got another laptop and named it identically to the first one...so it acted as the first one but without a pairing. Again, the phone ignored the request until I said it could pair (a manual interaction) and the keyboard required me to type in the pin from the keyboard. Btw, my laptop also doesn't allow pairing without explicit user intervention.
So great, they found a theoretical vulnerability, but one with an easy work around and one vendors have already seemed to predict. Besides, how useful can this be? As someone said, if you see someone stalking you, you have bigger problems. And if your keyboard stops working because it's paired to another device, it's unlikely you're going to be typing anything on it.
Find something else to worry about...
...even when security features are switched on.
Why does everything come with security 'features'? Shouldn't everything be as secure as possible out of the box? If it was made inherently secure, it wouldn't need 'features'.
"For Great Justice."
FTA: The first step requires the legitimate users to type the same secret, four-digit PIN into both devices.
Pin length isn't fixed in bluetooth.
It can be anything between 1 to 16 numbers.
Sure it's easy to crack if you use one or two digit length,
but with 8 digits or more, it will take much longer to crack using brute force.
Besides, bluetooth always requires authorization before allowing network/dialup access from the modem device, even if it's already paired with the client machine.
Annoying, but gives extra security step.
There are no atheists when recovering from tape backup.
It is often very easy to find the pin code, as most peripheral dumb devices such as BT headsets come programmed with the pin set to 0000 and cannot be changed.
Mike
...seriously. The giveaway is the 4 digit pin. Of course it's crackable. You don't even have to look at the specs to deduce that.
Doesn't it make you feel good to know that our freedoms are protected by politicans, lawyers and journalists.
By looking at the timing results for their fastest algorithm (algebraic manipulation), it appears that adding a single PIN digit increases the calculation time 10-fold.
Just by making the pin 8 digits, this crack would take over 12 minutes.
And then there's this little tid-bit:
"Note that the attack, as described, is only fully successful against PIN values of under 64 bits. If the PIN is longer, then with high probability there will be multiple PIN candidates, since the two SRES values only provide 64 bits of data to test against. A 64 bit PIN is equivalent to a 19 decimal digits PIN."
-Mike
Schrödinger's cat is not amused—maybe.
Paris Hilton
Want to improve your Karma? Instead of "Post Anonymously", try the "Post Humously" option.
With the relibility of bluetooth, peer reconnect is uncommon unless a guy w/a big antenna is sitting right next to you trying to disrupt your connection (as mentioned). It's not the PIN nor encryption at fault, just the [lazy] way of reconnecting.
As is, I'm not losing sleep over this as I don't have a public-transit commute
Well, as long as you don't get stuck in heavy traffic, you'll probably be OK. I can imagine guys right now, imagining and designing automated systems so they can drive around, hijacking devices, doing nefarious things. Basically a money machine, ala:
1) Create Automated Bluetooth Hack Box
2) ????
3) PROFIT!!!
Mod down people who tell people how to mod in their sigs
and most wireless hacks, actually is this:
Obviously, we all need to carry a small EMP generator and periodically, without warning, suddenly shield our device and the device we're trying to legitimately connect to, then POW blast the EMP and destroy any "outside" devices that may possibly be listening it.
No, this is not impractical. Please begin taking these precautions immediately!
Few people realize how Apple's responsible for many of the technologies that plague personal computers today. For example, the first computer virus recorded came out in 1982 on Apple hardware and exploited flaws in Apple's early operating system. Apple also had a key role in the development of the MIME attachemnt protocol (via their NeXT subsidiary) that allowed malicious executable software to be mailed around with ease.
Best Buy can have you arrested
Sounds like we shoul start putting quote marks around the word "secure" whenver we talk about Bluetooth devices.
Third is still very close!
You can't brute-force 10,000 combinations with a good hope of succeeding if you only get three tries. Even a 25 second wait after 3 incorrect PINs would make the attack last a full day.
Actually the "brute force" is not done by communication so the victim cannot stall the attack. The brute force attack is entirely computed in software by the attacker's PC. The attacker simulates all 10,000 combinations until he/she gets a match with what was sniffed during listening to the re-pairing processes. The attacker only sends two communications to the victim's device: 1) a "I've lost the PIN, lets re-pair please" message. and 2) a successful here's the valid 128-bit key. Thus, the victim cannot make the attacker wait 25 seconds between tries because the cracking attempts are all done inside the attacker's PC.
That is what makes this attack so evil. The victim only sees one message (if that) and probably thinks "Oh, one of my Bluetooth devices has glitched/crashed and I need to re-enter the PIN." Given the general unreliability of most computing devices these days I bet the victim is not even that surprised/suspicious of the message.
Two wrongs don't make a right, but three lefts do.
I'm about to buy a cell phone. I was looking at a couple blue-tooth phones, just to keep the cell phone viable for a longer period of time. Should I refrain?
Re the 19 decimal digits thing: what % of PHBs do you think you'd be able to convince to use a _20+_ digit code? I believe that code has to be entered at each repairing?
Also, the attack is trivially parallelisable (it's bruteforce, hence the exponential curve). Even without additional caching à la MD5, the amount of data describing the data is extremely small, and could easily be sent over the internet. 64 or 128 P4s aren't exactly hard to come by. Moreover, it seems like the researchers haven't used SIMD extensions. SSE2 supports a 2x64 format, and it seems like that could potentially nearly double the throughput. Admittedly, it'd complicate the parts that rely on LUTs, but, given enough memory, I believe that there are bit swizzling routines that'd allow to mask and shift only part of the register (it'd multiply the table's size by 4, though). This isn't an attack I'd dismiss as impractical, for both human and technological reasons.
Try Corewar @ www.koth.org - rec.games.corewar
I'm glad I didn't get a bluetooth phone. I almost decided to get one, but being a security geek, I wisely thought better of it.
Glad I made the right decision... the problem is that a Cell phone should be a phone. Something you make phone calls on... adding all that other crap to the phone (camera, PDA, etc) is really not something I would need.
I just hope it will be possible to get just a phone if someone wants one.
It was the Waterhouse family.
So they are called "Cryptographers" now...
The first phase of the attack requires me, the human victim, to go through several steps. First and most important, I have to notice that Bluetooth isn't working. I then have to read the tiny screen of the phone to see what the error is, and decide that pairing is necessary. I then have to go through the entire manual pairing process, reading cryptic instructions and navigating unfamiliar menus with a thumb-joystick thing. I'm not so suicidal as to attempt any of the above from the driver's seat in traffic.
John
Can people use this hack to get my password that I'm typing on a wireless keyboard. (Distance issues aside.)
Essentially, yes, although it's a bit complex. Basically, they can send out a packet that forces your keyboard to stop working. At this point you have to re-pair your keyboard, so you type in the PIN and re-pair it.
Now, the PIN is never actually sent, but by capturing what *is* sent between your machine and your keyboard in setting up that secured connection, and then running a program to brute force it by trying all 10,000 PINs to see if that would produce what they captured, they can figure out the PIN. And then, yes, they can decode everything you type.
- Give a man a fire and he's warm for a day, but set him on fire and he's warm for the rest of his life.
Others interfering with your business isn't a problem when you aren't allowed to do anything worthwhile.
Freedom Above All
"And we have seen and do testify that the Father sent the Son to be the Savior of the World"
1 John 4:14
I'm pretty sure that just about everything will be hackable in some shape or form for the remainder of your life times :-/
[quote]I'm pretty sure that just about everything will be hackable in some shape or form for the remainder of your life times :-/[quote/]
They can't hack into my brain becuase I have a tin-foil bike helmet.