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The Black Hat Wi-Fi Exploit
Joe Barr writes to tell us that while many have heard that an Apple was exploited in order to install a rootkit at the recent BlackHat security conference, most people don't know the details of how it works. This is no mistake, it seems that the researchers who demonstrated the flaw were intentionally vague. Some theorize that this is in response to the real or perceived threat of legal action similar to the situation with previous Blackhat presenter, Michael Lynn.
Perhaps it is the exploiter who is better off with the Atheros based WLAN card? Maybe it is still possible to exploit any other WLAN card, but the attacker may benefit from using some WLAN cards over others as the attacking host platform (not the attacked target platform). Reference: http://www.ktwo.ca/security.html
The current exploit was intentionally vague so that attackers would not have the upper-hand. The previous researcher mentioned was arrested for something prior to his presentation; I do not correlate the actions together.
The machine unmakes the man. Now that the machine is so perfect, the engineer is nobody. -Ralph Waldo Emerson
ScuttleMonkey writes to tell us that apparently the 'plot-thickens' as some guy somewhere emailed that some people are 'theorizing' alternate motives for the Blackhats keeping wraps on their so-called 'exploit' (that they tried unsuccessfully to smear a OSX security with).
There is no new substance. This bone has been gnawed clean already. Sounds more like some people are making excuses for something...
www.tribalnetworks.org - helping tribal people around the world to own their own means of high-tech communications
I don't get it...
If they really cared one way or another about seeing the issue fixed, why not show up at WWDC, meet w/ some of the Apple engineers onsite, demo the issue, and work with Apple towards a resolution?
Why the cloak and dagger BS? "We're afraid.." Meh.
Never-mind using a 3rd party Wifi device and not demoing the built-in hardware being exploited.. never-mind covering up the USB device w/paper for some unknown reason.. If it's so easy to do with the built-in hardware, why not do that in the demo? Why use the USB part?
And, one thing I still miss out of this.. What sharing service needs to be active? It's one thing to connect to the WiFi on a computer.. But some service has to be active for file system access.. SMB? AFP? SSH?? Given the use of 3rd party WiFi hardware, and the default config of MacOS X to have all sharing services turned off.. Does this work when a Laptop is already connected to a network? Um, what are we really looking at here? Allot of questions, with very little info..
Something smells fishy... Shrug.
This is BlackHat, folks. They've probably hacked the water fountains to serve Bawls instead of water -- let alone installing a rootkit on a laptop.
Slow news day, I'd say.
Paleotechnologist and connoisseur of pretty shiny things.
Well,
I don't see that post as flamebait so much as a user looking for facts.
I agree. We're still low on facts about this. More questions than answers...
What about full disclosure? Contacting the hardware and software vendors affected?
Cloak and Dagger BS sums it up nicely actually.....
meh
Well, extrapolating the facts from different sources seem to point to following theory:
WLAN device driver buffer overrun exploit allows attacker to run root-kit installer code.
Just a theory.
And here I thought it was the black hat wife exploit, guess I'm not gettin' any from the missus tonight!
Somewhere, a person is gaining unauthorised access to network or computing resources that they are not supposed to have.
We will report further details as they happen (...happen to get cleared by our legal department, that is!)
The presenters clearly got paid off by apple.. in the defcon talk they were whinging about the metasploit guys being offered $80,000 to $120,000 for unreleased exploits and they weren't prepared to release the code to the emails they got offering $10, $100, $1000 for the copies of the exploit
That's why in the video they used a "generic" wifi card when they admitted the standard apple wifi driver is broken as well
They said they haven't released the code because "they need to check all the apple platforms that are effected" IE they are waiting for apple to deliver them a whole bunch of free hardware
These guys were complete sell outs -- no live demonstration because they were afraid that the WIFI would be sniffed at DEFCON..... so coming to a full disclosure conference they are basically saying they don't trust disclosing to the attendees...
In the video they call the script "bad seed" so it's probably something to do with a PRNG in the crypto somewhere (or IV)
If this exploit exists on other platforms? Like say, the free Unix-clones like FreeBSD or Linux?
-- Linux user #369862
For those that couldn't make it, here is a video showing the exploit. http://video.google.com/videoplay?docid=-441573595 8080028817
Michael Lynn? As long as these guys didn't decompile proprietary software and put the source code in a power point presentation, I think that there's not much of a comparison.
First hand::Ellch talked a lot about the timings and the reactions of wireless cards to certain packets, as well as the need for a less fatty and feature full tcp/ip protocol. From the talk it sounded like Maynor developed the particular exploit. Ellch talked about his tool fuzze. Ellch's goal was to fingerprint particular wireless users and the driver model they were using....(to decide what Metasploit exploit you'll use this week) If I was a wireless guru, say like some of the other thousands alive, I could make a prediction. If they don't release the exploit soon, someone else will develop an equally powerful exploit into the wild. Buffer overflow the stack..... It's too fat and does more thinking than it should. I say patience is key. Even when they do develop the patch, how many coffee shop users don't apply patches? The biggest weakness in the attack is the fact that it sounds like a proximity attack. If you're not within wireless reach to the victim, you won't be able to attack them. That's just a guess since the video demo of the attack shows the attack from across a desk and not across the office. Cantenna anyone? Wifi-shootout?
I think the comments about Apples image are off. This was a third party card, NOT the built-in apple one. So it was probably based on a different chipset than the one Apple uses - otherwise they could just have used the built-in one.
So, which card was it? Considering that most companies only threaten legal action, and researchers usually ignore the threats, a good guess that this is a company that is known to not only threaten. One that ISS had problems with before. In short: I bet it was a Cisco card. Not an apple card but a Cisco one.
Right now Flogging a dead Story has been modded down to -1 Troll, which seems absurd to me. He points out that the story is thin and links to a prior article which already covered this topic. Trolls make wild accusations without anything to back them up. This wasn't a troll. Wish I had moderator points.
Read the EFF's Fair Use FAQ
Now I'm a big fan of a policy of eventual public disclosure of exploits. The behavior of many big companies have shown that without the pressure of public knowledge of an exploit they will drag their heels about fixing the exploit. However, it is undoubtable that publicly making availible details of an exploit without giving vendors a chance to create a patch increases the number of attackers who are able to execute attacks against that vendor's customers.
Now there are reasonable people who believe this increased danger is pretty much always offset by the benefits of public knowledge of the risk, i.e., a vulnerability you know about is sufficently less risky to justify disclosure. However it is disgustingly biased and misleading to not even acknowledge that some people and companies might reasonably believe total public disclosure harms the end customers. This is especially true when we are talking about the difference between revealing the existance of the exploit and revealing info that might enable someone to copy the exploit.
Moreover, I didn't see the slightest evidence that it was outside pressure that caused this pair not to reveal the details. The tone of this cnet article seems to imply they made the choice themselves to be responsible which seems totally reasonable.
Also I don't understand who would put this pressure on them unless it is the network card manufacturer. Macs, linux and windows machines are supposedly all affected so no one company would take a PR hit relative to others. Unlike the case with the cisco vulnerability.
Yes it's true that vendors tend to be biased toward maintaining their good name. Just like real people they tend to be biased toward the answers that help them out but this is hardly dastardly. True I think they sometimes go to far and chill free speech and harm security research but this seems fairly rare and I see no reason to believe it is happening here.
If you liked this thought maybe you would find my blog nice too:
Bottom line, assuming the demo is not a hoax, it will work against *nix, Windows, and Mac equally.
A lot of people have posted so far saying, "It's OK that they didn't reveal the exploit, because it protects people from hackers until the fix is out." Which is probably true for the most part.
However, these guys have given almost no information about the hack, making it impossible to protect yourself. Does your wireless card have problems? Do all wireless cards have problems? What can you do to protect yourself? Should you avoid using wireless at all? Is it a remote hack that can actually somehow enable the wireless card (through a secret back door or something)? We don't know. And by keeping these details secret, companies are hurting end users.
It is good to let the company create a fix before the exploit is released, but it is also good to give the user enough information to defend himself.
Qxe4
From the presentation... it seems that he didn't have a root shell, but only a user shell on Apple. Why just play on the user's Desktop? He should of edited some serious files like /etc/shadow, /etc/password or /usr/local/etc/sudoers. He could of at least used the "say" command in the demo to have the Mac say that it had been owned by Johnny Cache. That would of been a nice touch.
My main reason for believing that he had the logged in user's access is due to the fact that wireless is not system wide on Apple, but is started when a user logs in. If you change users(fast user switching etc...) then all your network connections drop as the wireless is restarted with the new user.
Some have theorized that if you don't quote your sources, then you're just full of shit.
If you were blocking sigs, you wouldn't have to read this.
"I asked Lynn Fox, Apple's director of Mac public relations, two very direct questions. 1. Are Apple MacBook users at risk using their built-in Wi-Fi capability? 2. Is Krebs' Washington Post report about Apple pressuring researchers not to reveal a MacBook Wi-Fi vulnerability/exploit accurate? I've received no response to that query. Nor do I expect one."
What is more likely: (A) A vulnerability exists in at least two WiFi implementations (some external card, and Apple's internal Airport), which allows to compromise systems independent of which operating system is running, or (B) two guys who want their fifteen minutes of fame doctor a video, claiming that they can crack any Mac with WiFi within 60 seconds, conveniently being so vague that nobody can verify or refute their claim, adding in a bit of conspiracy theory (pressure from Apple) on top of it?
Some theorize that this is in response to the real or perceived threat of legal action similar to the situation with previous Blackhat presenter, Michael Lynn.
Because we all know how trustfull and very nice people blackhats are, and how they wouldn't do stuff like purposly withhold information that they can use/abuse....
If anyone is guilty of "depraved indifference", it's the people who've let this vulnerability remain unaddressed for so long, not the people who let the public know that they're at risk.
My sig can beat up your sig.
I think a security expert needing some attention mentions Apple. I think being vague is probably motivated by some dishonesty.
Without any detailed disclosure, sure, the craftiest people will determine how to perform said exploits. However, there are very, very few of these compared to the script kiddies that will show up if you hand out the source and/or a road map to every Tom, Dick, and Harry. At least they're giving Apple (and others) a chance to address the problem by pointing out that there IS a problem.
I'm not buying the people who are upset at a lack of full disclosure because they are "unable to protect themselves". If there was a way to protect yourself, sure, perhaps you could tell people how to do it. However, judging from the presentation itself (at Defcon), there really IS no way other than mutilation of the driver itself (see the slide with the nintendo DS) to quickly defend one's system. Not only would this significantly break a lot of things, most users wouldn't know the first thing about doing it.
The root causes as outlined in the presentation were a combination of a poorly planned and thought out protocol (802.11) and a quick-to-market rash of sloppy driver implementations, and it's going to take nothing less than at least a driver patch (or in a fantasy world, an overhaul of existing wireless protcools...802.11 lite if you will).
So quit accusing the presenters of being motivated by greed, stupidity, or other such notions - the best way to secure users at this point is to speak with the manufacturers directly and attempt to achieve a patch, not to detail how to break in to every last miscreant on the planet. The authors are starting to do this by their dealings with Apple.
Oh, and for those of you that missed the FAQ at the end of the presentation:
-Yes, it affects the kernel, which means it's >= root/Administrator on any system
-It's a driver/spec implementation issue, which means it's not an OS-specific problem. The use of an Apple machine in order to show that "any" platform is at risk was meant to illustrate this.
-The money slide was a joke meant to show how lightly many people were taking this issue. I have no way of proving the intentions of the presenters, of course, but I believe this was the case - they stated their intention was to get this problem addressed through discussion, not money.
All in all, easily my favorite defcon session (unless you count the shots of 151 distilled through peppers). Thanks, guys!
The presenters were very specific. The security hole discovered is below the OS level and is in the drivers. Drivers are written by multiple parties and have always been a vunerable part of the system. However, before you had to be physically connected to the system to exploit a driver hack. That itself made drivers pretty secure. After all, not too many people install hard disk drivers they get in random emails. With WiFi, you no longer need a physical connection, and therefore the danger. Mac, Linux, Unix, BSD, and even (gasp!) MS-Windows are all exploitable to this hack.
This exploit was kept underwraps to allow vendors to release security fixes before the exploit spreads to every two-bit kiddy scripter around. It doesn't make much sense releasing information on how to implement this exploit when there really isn't too much you can do to stop it. It's the reason why the presentation was done on video and not live.
Of course, once the exploit is known to exist, it is only a matter of time before someone else finds it and implements it. I already know at least one person who is on his way to duplicate it, so the vendors better hurry up and fix the security hole. Apple and Microsoft can't take their merry ol' time fixing this one.
Really, look we know how to make a bomb...
See, you take some playdough and mash it up until you have this nice grey colour, and then you poke some wires it in and add batteries.
See? Watch this video and you'll see it go boom.
(Show video with big explosion).
See? We have to ban playdough as it's dangerous.
That is about the credibility of using an add-on card to prove that there is an available exploit in a particular laptop that has built in wireless. It doesn't matter if it's true or not, they presented it in an unbelievable fashion.
Personally it wouldn't surprise me either way; but their method is unconvincing. As security researchers they should know that.
In the video, David Maynor says they will be hacking a 3rd party wireless card and holds up a PCMCIA wirless card. He the procedes to "insert" this card into the left side of a black MacBook. You never actually see him put the card in the machine.
There are no black MacBooks that have a expansion slot for 3rd party wireless cards. Let me repeat that. There are no black MacBooks that have a expansion slot for 3rd party wireless cards. The closest thing to a PCMCIA slot in the MacBook is the new ExpressCard/34 slot which is only available on the MacBook Pro and are not available in black.
Maynor faked the whole thing.
Bottom line, assuming the demo is not a hoax, it will work against *nix, Windows, and Mac equally.
The easiest way to show that would have been to demo it on more than one platform. It would have been more work for them, but not much more. Going from OS X to Linux or BSD should be easy compared to the effort of doing the exploit the first time.
At the moment, if the demo can be trusted, we know the exploit works against OS X with a third-party card installed. Everything else is speculation.
To a Lisp hacker, XML is S-expressions in drag.
Considering that Intel released a security report for their drivers in recent times that a malicous attacker being able to have this exploit available to them, I'd say the odds are good that Occam's Razor cuts the other way. One must consider that there's another CPU running in there (or more...) doing the actual work of the WiFi device- it can be exploited too if there's a design flaw in it's firmware or in the hooks the OS uses to talk to it.
If that's the case, there's nothing you can do to protect yourself except not use the device.
I'm not going to say they're not guilty of a hoax, but considering all the details- if it is a hoax, it's an awfully believable one based on all the other information floating about.
I am not merely a "consumer" or a "taxpayer". I am a Citizen of the State of Texas
'' Well, extrapolating the facts from different sources seem to point to following theory: ''
There are no "different sources". There is one source, which got duplicated.
The demonstration was done via a video, not live, because if it were done live the audience members would have sniffed the traffic and figured out the methodology.
There was no mention of not disclosing because of possible prosecution or arrest.
http://www.technewsworld.com/story/52254.html
Why no attention to Microsoft's most secure OS ever getting hacked at the same conference?
-- Boycott Shell
If the bug is in the firmware, you'll be the last to get a fix.
If I can take over the card's internal CPU (probably running a tiny real-time OS) then I can use that to write anywhere in memory. I can patch any part of your kernel I like. It doesn't matter if your driver is good or not.
no, the researcher doesn't want everyone with a wireless card to get their boxes hacked. it's called "responsible disclosure". The hardware manufacturers have been notified of the issue and they are working on driver fixes. once patches have been released and users have been given a chance to patch, the details will be released.
Why is this conference still being held in the United States? To me, it would make much more sense to host it somwhere where law enforcement is less likely to hassle people.
--"Machines are vulnerable if they have wireless enabled and are set to connect to any available wireless network". This is enough information to secure your system. Simply tell it not to connect to any available wireless network. Only allow it to connect networks you have specified. Tada. No cash needed for this fix.-- This is wrong. The exploit is designed to attack any wireless card that is actively scanning. It does not matter if you are on a trusted or untrusted wireless network. According to the researchers, right now the only way to defend against this attack is to completely disable your wireless card and run wired. Also, I am an apple user. I find it just amazing at how ignorant a lot of the apple users are acting in how they respond to the exploit. OS X is exploitable as is any other OS. It is not impossible. People who use Macs should almost be flattered that they decided to run this exploit against a mac because it is saying "if this works here, it could work anywhere." That is why the researchers chose to run it against a mac. OS X is a great OS, BUT IT IS NOT PERFECT. Get over it.
Some Crackers have been doing this for a while, (we are way behind) look within your disk formats and OpenFirmware/Mac, Bios/PC, crack once - stay forever.
Time to start really paying attention, look for "bad boot blocks" for pre boot networking prefs.
This guy's got a clue:
http://www.securityfocus.com/columnists/402
Check the comments too.
Think about an intentional miconfig of your monitor settings (UNIX) now.
Required reading:
Reflections on Trusting Trust
Ken Thompson
http://www.acm.org/classics/sep95/
~hylas
Does anybody mention whether this exploit works on PPC? (Did I miss that?)
So no, it's not speculation that exploitable on other platforms, because the presenters themselves said it was, and specifically said they ultimately chose to demo it on the Apple platform for the reason stated above.
Oh then it must be true!
Until they, or someone else, demos it on Windows or Linux, it is just speculation.
SteveM
Come to think of it, a bigger question than whether they can make an exploit for PPC Macs (assuming the firmware is fat or something, I suppose), is whether they expect to be able to build an exploit that will work on openbsd.
If they found a vulnerability in a common firmware used by more than 1 manufacturer (Proxim, Atheros, whatever), they could get any model wireless card to tattoo all over the host memory using DMA. Drivers have nothing to do with it.
The vulnerability might be OS specific in that the payload and where it needs to go to exploit the system will vary from host OS to host OS.
THIS THING CAN TURN ON A DIME, MACROSSZERO STYLE ALSO FUCK BETA, ~NYORON
It may not be a firmware bug even, but an 802.11 _implementation_ bug that every vendor they've tried (thus far) seems to have included. Some kind of unhandled condition.
And since nearly every wireless card out there is an ARM7 running some kind of firmware attached to a radio, all they need to do is leverage the implementation bug into a stack smashing exploit that works ON EVERY ARM EMBEDDED WIRELESS CARD. It is likely that there is a recursive function with a similar structure for multple firmwares (since they are all implementing a fixed protocol in similar embedded environments), which if can be tripped up by a malformed packet reliably, can be used as the common injection point for exploit code.
So you've got ARM firmware exploit code, which uses a stack smash. You blast the wireless station with malformed packets attempting to get it to trip on the buffer overflow. If triggered it would in turn load (potentially) card specific host insertion code, which in turn injects OS specific exploit code into the host memory.
Boom: multi-card, multi-OS exploit. Thanks to the consistent firmware environment on each wireless station.
THIS THING CAN TURN ON A DIME, MACROSSZERO STYLE ALSO FUCK BETA, ~NYORON
I stole the "tattoo" bit from a term used to describe how NT4.0 group policy used to work.
Your Administrator would put registry settings in the NETLOGON share it would "tattoo" all over your host's settings, erasing whatever was there.
You could go back in and undo the changes if you wanted to (they aren't persistant like Group Policy Objects) but it was as painful as getting "old ink" removed.
The new GPOs are much better, they don't muck up your registry, they just overlay it. So it's like getting Henna or a press-on.
When a device initiates DMA and it is controlled by firmware, your precious precious memory is at the mercy of the firmware authors. And if the ink slinger (the firmware) gets schizo on your ass, well, you're waking up with a Unicorn impaling a baby on your left buttock.
And these black hatters are whispering in this guy's ear.
Wow I can really stretch an analogy out. GO ME
THIS THING CAN TURN ON A DIME, MACROSSZERO STYLE ALSO FUCK BETA, ~NYORON