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Exploit Based On Leaked Windows Code Released
mischief writes "A post to Bugtraq from SecurityTracker.com reports an Internet Explorer 5 exploit that has been released based on the Win2K code leak: 'It is reported that a remote user can create a specially crafted bitmap file that, when loaded by IE, will trigger an integer overflow and execute arbitrary code.' Only affects IE 5 apparently, but still - it didn't take long!"
Oops... we just gave MS a chance to say keeping the source secret keeps flaws like this secret as well. :)
Just to those that couldn't get access to the source code. Some people with access before may have known about this for a while. Not that we'll ever know.
...if the code was open from the start, how long would this flaw have lasted?
If your theory is different from practice, then your theory is wrong.
I for one am truly alarmed and cannot wait for Microsoft to start the repairs; but then again this is good news for MS programmers looking for OT.
It was only 15% of the source code which leaked out, yet it will show MS in the weeks to come just how the Open Source community operates. I forsee them working over time to provide updates to the numerious vulnerabilities which will arise due to the leaked code. This here is just one example. There were some what, 3 million lines of code in the leaked source. It is just a matter of time. Hopefully folks will report the vulnerabilities which they find, opposed to exploiting them.
My Thoughts, Kyndig
Actually I think that, if Microsoft doesn't lose it's customer base to all the exploits found, it's going to make Microsoft stronger. Think about it, right now Microsoft is receiving the same kind of security review that makes OpenSource products so strong in the first place. Granted, it's coming at a very high cost, but their source code will have much fewer bugs when this is over.
They can if the tool you use to open them is ridiculously poorly designed and permits buffer overflow (i.e. IE).
If your theory is different from practice, then your theory is wrong.
"1. load int from char array
2. check int against sizeof(yourbuffer)
3. reject if greater
Not exactly a challenging task
It all goes to the quality of the coder. This is just plain bad code. I learned how to write something to check these kinds of things in middle school.
Evolution or ID?
If you were to embed myDoom after the overflow area in the bitmap then when outlook opened the file using ie's render could one have my doom that didn't even need to have the end user open the file? It would just execute replicate, then piss people all to hell? For that matter could I include the windows equivalent of rm -rf / ?
There is nothing wrong with being gay. It's getting caught where the trouble lies.
My feeling is that, in the context of preventing attacks, it's bad. With linux, discovery almost immediately leads to a fix cos it's the same volunteer community does the finding and the fixing, but Microsoft doesn't let the Bugtraqs of this world help. It's going to buckle under the strain of too many bugs at once.
:)
Of course, from the point of view of converting everyone to Linux, this can only be a good thing
For the love of God, please learn to spell "ridiculous"!!!
Please...you might as well say that BSD is dead. Nobody is happy about all the ruckus that the whole affair is going to raise, but it's a little early to pronounce Microsoft dead.
-h-
So does that mean that all the users that use outlook could also fall prey to this? Send out spam with image and if the outlook user has auto preview on, which they probably do they now can be exploited by whatever code. That would be an interesting concept that would lead to alot of trouble. Sure IE5 is old...but lots of people still use it.
No system is 100% secure be it Windows or Linux.
When people have access to the source they can more readily find exploitable mechanisms in your code. This is a GOOD thing because you want to know that your system is exploitable, how it is exploitable, and (which is the case in many open projects) how to prevent that exploit.
Any form of content (not just scripts and ActiveX controls) can be used to exploit a weakness in a system. A security strategy that involves simply filtering content is a weak one.
The open source community can be a powerful friend to any organization willing to take the chance on their code being available to others.
Whether it's finding exploits, bugs or whatever; anything that anyone does with it will eventually make Microsoft stronger. If it's a security problem they 'll fix it. Maybe Microsoft is trying to capture open source developers and their free services; I don't know.
What I don't want to see is Microsoft making improvements on their product based on this experience. I don't want to see as much as two adjacent assembler instructions from it end up in Linux.
If you want to do something constructive, run the 2.6 kernel and start making the supporting software more secure. Don't waste your time supporting losers like Microsoft who demand your money up front and then deliver whatever crap they feel like.
Just ignore it!
"Can there be a Klein bottle that is an efficient and effective beer pitcher?"
You really are going to try and blame this guy for "possibly [exposing] thousands of users to a root exploit"?
There are certainly other ways to go about reporting bugs (not that Microsoft will listen to any of them), but blaming the messenger for pointing out that the castle wall is full of holes is a bit misdirected if you ask me.
Cheers
~Dalcius
Rome wasn't burnt in a day.
You laugh, but I won't be the least bit surprised when this very logic finds its way to the receptive ears of less-than-tech-saavy corporate officers...
"Linux? Good god no, man! Didn't you see what happened when just a bit of the Microsoft source code got leaked? I thought you were up on these things!"
Obliteracy: Words with explosions
That was interesting to read. It made me wonder who the people are who come up with these exploits. This person is obviously very immature, but also very knowlegable about programming to spot something so quickly in so much code. The question is, is this a ridiculously knowledgable 13 year old, or a well-seasoned older programmer who has the social skills of a 13 year old?
It also shows that ms does their job.
.net or you don't programm at all. Its the price you pay for native compiled code and the main reason people are turning their backs on it.
When microsoft declared security as their main goal ie5 was the current browser. ie6 has it fixed so they obviously wen't trough their stuff to fix it.
Its very true that bounds checking errors are very easy to prevent but if you say its sloppy programming to have errors like this in your code you either work in java or
Even, for an IE hole, this is pretty severe - now worms just have to send html emails with an img tag that points to a specific bitmap and voila: anyone who uses an mshtml based email client(including webmail) and hasn't updated for a while gets infected just by opening the message.
Sure, sooner or later hotmail will stop showing bmps in messages and issue a warning like "if you get a message, do not open it, but delete immediatly", but hey, I bet the amount of worm emails in my Junk mailbox will increase drastically in the next couple of weeks.
Join the elite! Post at score:2! Ghostwheel is online.
Burn some Live CDs to hand out to friends,
n ux
family, co-workers. Introduce them to Linux and
warn them of the dangers of LOOKING AT IMAGES
using Internet Explorer 5.0.
There are many good ones*. Personally I fell in
love with the Knoppix 3.4 c't edition with the
2.6 kernel -- using it gave me my first
experience of non-stuttering KDE with heavy
loads, looping MP3s and lots of useable features
(except detecting the Dell Inspiron 5150's on
board WiFi -- not Centrino).
Pick several, spend a few bucks on good CD-R
discs, make a nice label with "do exactly these
steps" instructions on the label.
It's not about world domination, it's about
stopping the theiving cracker spammers from
gaining more zombie Windows boxes to do their
bidding and ruin the Internet for the rest of us.
* start here:
http://www.google.com/search?q=live+cds+li
-- @rjamestaylor on Ello
yes, but that's assuming that everyone who finds a simple exploit like this one actually reports it. i can imagine that there'd be a number of black hats that will find and use these kind of exploits and not tell anyone how they did it.
but i am happy that this leak happened. it just shows that the code should be out for peer review from day one. security-by-obscurity is second only to security-by-telling-people-what-not-to-do. (e.g.: "don't open that door, there's valuable stuff in that room")
Maybe there's something that I'm misunderstanding here. You're suggesting that he's just a messenger -- nothing more? I completely disagree. This person posted an exploit. I'm not sure how it is where you're from, but from where I sit, posting an exploit is on an entirely different level from simply telling someone that their software is full of holes (including how and where).
To use your analogy, rather than being a messenger telling the king that his castle walls are full of holes, this is a little more like designing a weapon to destroy your castle walls, and posting the plans in every neighboring town (which somehow manage to automatically build the weapon, provided you have the right tools). All the recipients have to do is tell the device to build itself, point, and fire.
The point is that this guy was downright irresponsible and should be treated as such. Any sane king would have beheaded this person in a royal heartbeat.
-Turkey
Being that the code leaked was Windows NT 4.0 and
:) Didn't they originally clame they
2000 source codes, why are we seeing an issue
with IE 5.0? Just goes to prove how close the
browser was tied to the operating system.
On a cynical note, this only bolsters security through
obscurity.
had fewer bugs than open source competition?
With some 10% code or more leaked, there is quite
a bit more worry about their own peer-review process
or should I say lack of.
It's getting the same kind of security review - but none of the feedback. No white hat wants to admit to MS that they've seen the code, and black hats wouldn't anyway. All this may end up doing is increasing the number of "submarine" exploits out there that hackers use for their own benefit, rather tahn making super-viruses that make the exploit famous.
Last post!
Granted, it's coming at a very high cost, but their source code will have much fewer bugs when this is over.
There is only one problem: the source code is ilegal.
Most people who find and report bugs will probably never see this code, and if they do see it, they'll deny it. This means that most people looking at the source code for bugs are doing so for their own benefit.
It'd be very naive to believe that these black hats will release information about the bugs they found. In the case of this IE5 bug we can say that the guy who found it is probably a young fellow looking for m4d pr0pz.
IMO, this source leak is very bad for MS, for it will get the worst part of both, closed source and open source, worlds. In one hand, every bad guy out there can, and will, see the code, in the other hand every white hat is legally and ethically forbidden to look at the source.
Unless MS is trying to pull an SCO, I can't imagine a worst scenario.
But this IE exploit shows that the author was wrong on at least one account.
Wrong. He was right. This particular IE exploit has been fixed; it only affects an old version of IE. And IE is free, so there's no real excuse for not upgrading it. If I found a bug in an older version of an open-source app, and filed a bug report on it despite the fact that it had been fixed AGES ago in a newer version, I think I would be told to shut the fuck up and upgrade with little or no delay.
Quality, performance, value; you get only two, and you don't always get to pick.
Well let me ask you this... look at this brick wall. Now tell me which one of the bricks is actually a rusty piece of metal that just looks like a brick.
It's pretty simple to see this bug now that we're looking right at it. And it obviously was not too hard to find when specifically looking for index-checking bugs. But it's even easier to let something like this slip when you're a tired microserf adding code at 4am trying to meet a deadline. And with the limited resources at Microsoft (huge as it is), that have to be divided into all the different parts of all the different software projects, it's really a hard sell to convince someone to look through all the gazillions of lines of code that have "Just Worked" in the past.
It's easy to judge, but since we really don't know the environment in which this particular bug was introduced, I think we should cut the original programmer a little slack. (not completely, though. Some culpability is appropriate seeing as Microsoft took our money and should be somewhat responsible for the damages caused by the vulnerability of their faulty products)
You didn't need the source code to find that problem. I found it because I was creating compressed .BMP files and accidentally created one that crashed Win2K every time.
If Microsoft doesn't read Slashdot, that's their problem.
Fuck MSFT it's called bounds checking. e.g.
1. load int from char array
2. check int against sizeof(yourbuffer)
3. reject if greater
AHahahaha, you know you just made the exact mistake MS did. You're using ints, not unsigned ints. Reject if greater does nothing if it's less than 0, which would still cause an overflow.
It isn't all that difficult to narrow the search when looking for exploits like this. Its surprising (or maybe it isn't) that M$ never looked for them. At our shop, its common practice to detect dangerous code.
...
...then inspect the code for ways to read/write past the bounds. That narrows the search field quite a bit (ok, you'd miss arrays defined with #define symbols, but you'd catch the sloppy ones, which is what you want in the first place).
Just search for all stack arrays in the source...
$ egrep "\[[:digit:]+\]"
Combine a search as above with one for calls to strcpy(), strcmp(), sprintf(), [or any other C runtime/misc. function that fails to check input], and you have an even smaller lump of code to inspect.
So, the 13 year old wouldn't need extensive knowledge, just what you could glean from reading an article or two on buffer overflows. Still, I'd bet its a seasoned socially backward individual.
Anyway, good question to ponder.
Nobody knows how old the sourcecode actually is! Several people have used IE 5 and the exploit code does not work. The things in the code could have, and in this case, has, been fixed long ago!
You're seeing an example of one of the very few instances where goto is considered "acceptable" to use. Sometimes you code a function which winds up a lot of complicated state, and a failure halfway through requires that you "unwind" the partially constructed state. This is most easily accomplished by having a "bailout ladder" which can be jumped into (via goto) from various points in the code above.
The only other solution involves lots of code duplication, or very bizarre function calls such as CleanupMyState(&context, 6) which just ends up use a Duff's Device in a switch() statement to simulate the use of goto in precisely such a manner, anyway.
When you find that the cleanest way to do something is goto, then the solution is goto. What is the point in cortorting your code just to follow a piece of dogma that was only meant as a guideline anyway? Remember, the point is clarity, not adherence to dogma.
i dont see why everone is going crazy over this exploit. i mean really... microsoft actually has already done something about this... its called get the NEW version of IE. Don't get me wrong, I am a big open source supporter, but seriously... oss would have made no difference here. Basically people just have to keep up to date with IE and patches to get around this. Same as if someone, however unlikely, found such a exploit in a mozilla product... or some other open source browser. the fact that it is open source and someone could find the bug faster means nothing if you dont keep your software up-to-date. And no, most casual Windows users don't. and no getting them to switch to a 'nix OS wouldn't change that.
/. crowd have no idea what they are doing....
its really more of an education problem than a software problem. most computer users (not the
at least thats my 2 cents.
Matt
You have 1 Moderator Point! Use it or lose it! Is that a threat? -vapid
I think you might have your terminology backwards. Posting the vulnerability is a favor to people. Posting an exploit is a different story altogether. Since you have a hard time differentiating, let me try to help you out:
Vulnerability: "Hey, look -- I've found this hole in IE. Here it is, fix it. Everyone else -- this software sucks. Use something else."
Exploit: "Hey, everyone (script kiddies included) -- here's some code that I put together that exploits vulnerable boxes. You don't have to know a damn thing to root a vulnerable box. You can use this for anything, spamming, DDoS attacks, mining for credit card numbers -- it doesn't matter -- crack away, oh 31337 ones."
Now can you tell me which is more constructive? The exploit or vulnerability. Now rememeber that nobody finds an exploit -- they're all written. Vulnerabilities are found. I completely agree that vulnerabilities should be made public -- but as far as exploits -- you're dead wrong.
Now, if you didn't have you terminology backwards, your logic is just irresponsible. How is an exploit any more helpful than a vulnerability report to bugtraq? How could it possibly benefit anyone other than the script kiddies who will eventually get their hands on this code? People need another exploit in the wild like they need another hole in the head. You will still have an opporitunity to tell your friends and family about your disscovery -- only you'll have time to tell them to update their browser...not that they've probably been rooted.
PS -- next time, if you're less confrontational in your replies -- you will likely receive more friendly responses...ass.
-Turkey
Fuck MSFT it's called bounds checking. e.g.
1. load int from char array
2. check int against sizeof(yourbuffer)
3. reject if greater
Not exactly a challenging task. I guess they're too busy adding in all that crapware to actually code at least one thing right.
I guess you missed the original article, brainiac, but your code is flawed.
"Reject if greater" will fail if int is negative.
But hey, thanks for proving that you're as dumb as a box of rocks.
Coming soon - pyrogyra
Doing ANYTHING with the code, good or bad is illegal. So if we DID make a patch, we couldn't claim we did.
This is an exploit which effects Users, running a WEB BROWSER. Please tell me one single (however insignificant) thing a Normal User who is running a web BROWSER could possibly give half a fuck about which requires administrator privledges.
Seperate user accounts, securing the system itself, etc, that is _ONLY_ security-related when you are the administrator of a server and require your box be up 24/7 (or at least somewhat often)
Think about it for two seconds: You're a normal user, you're using your personal computer. Hell, you're using it to surf the web, this isnt any system which other people are dependent on having a high uptime or anything. You go to a webpage, and some arbitrary code gets executed.
What files could be effected? Well, you're running as a normal user, so luckily for you only the files which you give a shit about will be harmed, while the easily replaceable part of the system remains intact.
This whole "multiple accounts == security" line is pure bullshit extract. The files which a USER, not a System Administrator, cares about, are files which that USER created, downloaded, edited, etc. Files which the User has access to.
If some malicious code executes as root/Admin, so what? Your important files are trashed and you need to spend an extra hour reconfiguring your system? That extra hour or two doesnt mean squat compared to the years it may take to restore the files which you created personally.
"You Should Keep Backups anyway" is Irrelevant. As that can just as easily be applied to root-accessible files, the point is that non-admin privs are just as bad as admin privs on a personal system.
And this exploit _is_ talking about a personal system, unless you're in the habit of running IE5 on a high-priority server instead of the laptop sitting next to it.
-- 'The' Lord and Master Bitman On High, Master Of All