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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"
:)
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If it's a manual step, then it'll require education of the users to not pair their phones in public.
John
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 ?
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
...an excuse for my "adult" calls on my phone bills.
__free funny videos
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.
Nope, most security professionals want to fix bugs. There will always be enough holes in software to make our lives difficult.
:(
Bluetooth in and of itself is a fairly decent protocol for what it was originally designed for (ca. 15m range personal networking). It encounters a lot of limitations in the capabilities of how it is implemented (i.e. static shared PINs, etc.)
And you're mistaken about crazy hackers; I know of quite a few pretty top-end cryptographers still doing good research while employed as pet security bwanas by large banks, IT corporations, etc. Although, I don't know whether you could refer to "job security" when talking about an outfit like IBM research
Cole's Law: Thinly sliced cabbage
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.
Maybe I'm missing a beat here, but TFA says that the communications between Bluetooth devices ARE encrypted...it's simply a Bluetooth device's "heartbeat" that's unencrypted, and it allows for hacking.
Now, if they maybe wanted to use more encryption so the key isn't as breakable, that would be an idea...but it would probably mean more expensive hardware, and longer PINs.
My boss always says security and ease of use are on two opposite ends of a line, and with any system you have to put the 'x' somewhere. Bluetooth chose to plant their 'x' pretty close to the Ease of Use side, which cost them security.
But then again, if I see the little "B" icon on my v600 and my headset's not on my ear, I know SOMETHING's up...
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.
...add one of these bad boys and shake vigorously.
Mmm... phreaky...
That green slime had it coming.
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? \
RTFA. The hackers device tells the other device that it forgot the key. The pairing is deleted. The user has to re-pair the devices if he wants to use them again. The hacker can listen to that second pairing and use the previously discovered techniques to get the key.
by Mike Buddha -- Someday the mountain might get him, but the law never will.
... and a litany of new security issues. There is no "magic" technology. Get over it.
by Mike Buddha -- Someday the mountain might get him, but the law never will.
It doesn't resend the key. The problem is that an unencrypted easily spoofable message can force the device to renegotiate a new key. This renegotiation is the vulnerable state. Really this just makes the orignal hack easier to preform in that it can happen when at any time instead of initial pairing of the two devices.
Curse goodness when you forget use it...
Mike
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.