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GdkPixbuf Suffers Image Decoding Vulnerabilities
DNAspark99 writes "It seems Multiple vulnerabilities have been reported in GdkPixbuf, which can be exploited by malicious people to DoS (Denial of Service), and potentially compromise a vulnerable system. Personally, I wasn't concerned about this until I ran 'ldd firefox-bin | grep libgdk_pixbuf'" There's no official patch yet, but the article notes several Linux vendors have issued updates. Worth keeping an eye for those who use libgdk_pixbuf under other Unix-style operating systems as well.
More bugs. More fixes. More patches. This is the software cycle...
If you're not aware, gnome2 uses this library, so any gtk2/gnome2 applications you use are probably linked against libgdk_pixbuf.
update your systems...
sigh Time to tell the idealist in me to STFU.
-paul
Pistol caliber is like religion: everyone has their favourite, and theirs is the only right choice.
Well, they tend to be writing in C, and concerned about "performance". They thus leave out vital buffer checks. Given that computers are now 3000 times faster than when I was a lad, there's no excuse, any inefficiency is easily compensated for by the "ridiculous speed" of modern computers.
Either learn to write safe C or switch to a safer language.
There will always be vulnerabilities. Since people can't produce perfect code there will always be a way for someone to make a flaw into a vulnerability. Therefore there will always be patches and updates(relating to security measures). The only way to stop these flaws from becoming an issue, like this one, is to stop crackers. And good luck with that.
Free Ipods it's for real check out Wired then go to: http://www.freeiPods.com/default.aspx?referer=8533
Time to switch. Take back the Web.
Vote against shoddy software with your clicks.
It strikes me that it would be a good use of any spare capacity some search engines might have to search for image headers on web sites, that are attempting to exploit these types of problems.
Uhhh, no. It is simply "in vogue" to look for vulnerabilities in image format parsers at the moment. Is the trend not obvious?
Soon all the major image libraries will have been examined, all the bugs fixed, and the security gurus will move on to other things. And we'll all benefit from that, because the code will be fixed.
Bitching is counterproductive, don't you think?
The only places using gdk-pixbuf in Firefox for loading images are all for loading images from your local machine. No from-the-network code paths use gdk-pixbuf.
Last time I ran "ldd firefox-bin | grep libgdk_pixbuf". I was pretty worried that I had no frigging idea what the hell I was typing.
I find that alot of people I've worked with in software development have a "get it working, clean it up later" attitude. Usually basic error checking gets thrown in, but "hardcore" security often gets put aside in favour of other projects that need to be done. Thus, I think we end up with a fair amount of possibly shoddy code.
I've never done an audit, because I'm trying to write good code, and it's all I can do to be as "productive" as the others.
I don't think anybody seriously thinks "man, that could be a huge problem! well, nobody will notice".
-- Seq
Now your GNU/Hippie software is vulnverable what are you going to do about it?!
...patch it before the vulnerability is even announced... not six months later.
I was just using the Icesoft Java web browser and the Fluendo media player. These are both big applications written in 100% pure Java. They both don't have buffer overflows because Java doesn't have buffers (in the C sense). How many security holes do we need to see every week?
There's a particular comment which we'll see about a thousand times on this thread alone, the gist of which will be, "See? Even open source has bugs/security holes! It's no better than Microsoft!"
The reason we bash Microsoft for its bugs and security holes is not because they have bugs and holes; the reason is that Microsoft paints itself as the savior of computing, as software that will make your life infallibly better and easier, and along the way has made quite a lot of unethical business decisions. They basically brag about how uber they are, and then they release crappy software and frequently take forever to fix certain bugs (or simply never fix them -- e.g. PNG transparency in IE. What's it at, 3 years and counting? 4?).
The guys who write open source stuff like GdkPixBuf, on the other hand, have not (to my knowledge) done these things. They are thus not deserving of scorn; they write software, release it, and say, "I wrote this because I needed it. If you want to try it out, here you go. Have fun; I don't promise anything."
That's why we mock Microsoft for its bugs and not the GDK team.
(To be fair, I'm certain that there are some OS projects whose developers are as arrogant as Microsoft, but they at least do not have the unethical business history Microsoft does, nor do they (still!) have a monopoly on desktop OSes that they continue to abuse to the detriment of everyone except themselves. It's one thing to be an asshole when you're nobody important; it's quite another when you have a great deal of power.)
"Destroy science and religion. Science would re-emerge exactly the same; but not religion." - Penn Jillette, paraphrased
Firefox doesn't use gdk-pixbuf for drawing it's images. The only places using gdk-pixbuf in Firefox are loading a couple of images from your hard drive into the browser UI -- like the little Windows desktop icon that shows up in the download manager UI. This isn't remotely exploitable in Firefox.
--Asa
Fix it.
Actually, we can, that's one of the main reasons for the existance of open source.
well eventhough the computers are zillion times faster, the datastructures they have to deal with have gotten zillion times bigger and/or more complex.
Solving algorithm-deficiencies by throwing more iron at it is a short-term solution that is bound to come back and bite you in the tail sooner or later.
Learn to write safe C and make sure your algorithms are sound and healthy.
There are a number of very easy things you can do while coding to make it more secure. For example, avoid any non- "n" string function. Just get used to typing and using strncat and snprintf and the like instead of the unchecked ones. Little things like that can actually go a pretty long way.
Personally I think C is much too slow.
Relying on high level languages like C seems like a good idea because of development time and security but eventually program complexity will outpace hardware speed increases and you will be screwed!
A real programmer doesn't need to waste resources on bloated handholding crap like "C". A real programmer uses assembly to avoid writing bloated code!
There is no algorithm to do what you are describing (google for "halting problem")
You could run something like lint to catch common C errors.
Better than that though is to profile your code actually running, to see buffer overflows and leaks that actually occur (google for valgrind).
But most of these exploits are specially crafted input that produce buffer overflows. Typical input won't. So it is very hard to test for buffer overflows.
The only 100% way to work these kinds of problems out is to write code in higher level languages, so at least you'll get an exception and fail closed in the case of a buffer overflow.
But in C, the only way to resolve these problems is
1) Don't write code with buffer overflows (hard)
2) Find and fix buffer overflows in code review (harder)
3) Write good enough negative test cases that you find the buffer overflows (really hard for even a good tester).
if you didn't realize by reading the news in the last week, it doesn't matter how long your software is attacked, new bugs are found. Yes, guess what, even microsoft has vulnerabilities announced every month. Millions of eyes on the code can help and obviously it did. We didn't hear about the new virus out there in order to find out about this exploit, we just found out about this exploit. Millions of eyes don't prevent mistakes, they do help find them faster and patch them quicker. And of course, even this story is exactly what that is, they already have vendors with patches out for this problem.
hm..... seems Micrsoft, even with all its monkey-pounding, still doesn't have a shot in hell with fixing problems as fast as the open source community does. I'll stick with the box that doesn't stay vulnerable for as long.
As long as it's not a RAW screendump or uncompressed TIFF file or something, there's going to be some interpretation of the file's content to produce the human-consumable output. And it'll be based on a parameterized command stream. And if the interpretation of those parameters is not handled rigourously, or if the system does not account for every possible combination of commands, well then you're ripe for an exploit.
That's basically EVERY file format.
Even text can be dangerous. Ever heard of a terminal or ANSI bomb? (scroll down in link).
The only "safe" viewer is a hex editor. Or less (maybe, you get the idea).
THIS THING CAN TURN ON A DIME, MACROSSZERO STYLE ALSO FUCK BETA, ~NYORON
A more general prevention method is to use an environment that doesn't allow buffer overflows; as Java proponents never tire of pointing out, Java guards against this type of attack. There are C libraries which do similar things, IIRC; StackGuard was one such method, though it seems to haved faded into obscurity.
As to your suggestion of a static source code check for unsafe programming practices, there are programs that do that too. GCC itself includes a number of warnings that pop up if you use inherently unsafe C library functions, like gets() (which is buffer overflow in a can...).
Any sufficiently advanced technology is indistinguishable from a rigged demo
--Andy Finkel (J. Klass?)
Isn't it a bit odd that these libraries are failing on both Windows and Linux?
I wonder of someone has been stealing source code?
If tyranny and oppression come to this land, it will be in the guise of fighting a foreign enemy. - James Madison