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New Mozilla Firefox 1.0.3 Exploit
An anonymous reader writes "News sources are reporting that a 'killer' new Firefox exploit has been revealed today by FrSIRT who warn that this 0day exploit/vulnerability (as yet unpatched) should be rated as critical. Summary of the exploit: If a user clicks anywhere on a specially crafted page, this code will automatically create and execute a malicious batch/exe file. Proof of concept code supplied by FrSIRT."
Oh, wait.
Because THAT, with some documentation, would be helpfull. Still, as long as it doesn't create *nix r00tkits on the fly on my box, I'm on the safeside :)
Maybe it's time to accept Firefox has it's fair share of exploits?
And the best part, is the patch management system in Firefox is so damn poor (ie. non-existant), getting these patches distributed to end-users is a real damn chore (assuming they are distributed at all).
That's nasty! I'm glad that in Linux files aren't automagically executable when you give them a certain name :)
This was reported to the mozilla bugzilla a while ago. https://bugzilla.mozilla.org/show_bug.cgi?id=29269 1
Exploit summery? Well, the weather is improving but I doubt that the exploit caused it.
Bugzilla bug 293302 has been filed. A temporary fix has been implemented on UMO.
You converted 45 % of your family to Firefox?
Join the anonymous, help develop the network: http://www.i2p2.de
didn't work
They were already working on patching this, but it was stolen before they could finish and leaked to bugtraq with LIVE material in the exploit (it's not a proof of concept, folks!) and no explanation or advisory.
/. referers. Copy URL and paste in new to view. (Beware Slashcode's extra spaces.)
9 1 %lt; Original security bug (probably still blocked to outsiders to prevent someone stealing it before mitigation)
0 2 %lt; Duplicate (reported after leak)
h tml
Reminder: Bugzilla blocks
https://bugzilla.mozilla.org/show_bug.cgi?id=2926
https://bugzilla.mozilla.org/show_bug.cgi?id=2933
They are going to release a 1.0.4 shortly, I gather.
Still more timely than most of Microsoft's advisories... despite their earlier announcement. http://www.eeye.com/html/research/upcoming/index.
A^C^E, a Firefox security researcher, is claiming on Addict3D.org that this is a 0day duplicate of a leaked, known bug. He says, "I suspect that my server was compromised, and I am currently using my contacts to find the culprit and bring him to justice."
Also, bugzilla.mozilla.org is claiming they've been slashdotted. Go easy on em.
Uncheck Tools > Options > Web Features > Allow web sites to install software
Just curious, I downloaded the page and loaded it up on several systems:
Win XP, Firefox 1.0.3
Win 2k, Firefox 1.0.3
FreeBSD, Firefox 1.0.3
and none of them did anything. The javascript looks like it should save a file (c:\booom.bat) and run it which should echo "malicious commands here" and wait for a keypress.
Is this truly an issue with Firefox and not some other software? If so, any ideas why it doesn't work?
Disable JavaScript, or disable the "Allow web sites to install software" option [Tools - Options - Web Features].
Why would anyone run routinely with "Allow web sites to install software" enabled ?
FrSIRT Vurnerability Alert!!
FrSIRT will go down 2 minutes after the start of a brutal Slashdotting.
There's not many comments yet, but most of them have a similar theme: " Oh no, now Microsoft and Internet Explorer users can get payback for all the trash talk we've thrown at them." Then they rationalize it with, "But, MS and IE are way worse because of quantity, severity, and duration until patch."
Now think about it for a minute. Who are you really at war against? Security exploits and the people who would exploit them, or browsers other than the one you use and the people that use them?
This reminds me of the days when Mac zealots would get all freaked out every time PC's got faster. "OMG, this is bad news! Now there are 3GHz PCs for under 500 dollars!"
This really boils down to people rating the quality of Product A compared to the suckiness of Product B. Personally, I've been using Products A, B, and C for a long time. When there is a problem found with Product B, that really doesn't make Product A perform the task I use it for any better.
If you want to call yourself a truly knowledgeable computer user, then you have to acknowledge that Products A, B, and C all have their strengths and weaknesses and therefore have tasks their better suited for as well as tasks in which they're not the best solution.
If you look at it from the proper perspective, every time an exploit is found by good people before bad people have a chance to do harm with it then it is good for everyone.
This particular exploit also demonstrates how foolish it is to posture and sling insults. The whole time FF users slung insults at IE when exploits were found, this exploit was there lurking below the surface waiting to be found.
Let applications that are without exploit cast the first stone. Since that's never going to happen, argue your cause based on its merits.
Now we'll see Microsoft going "OMG DON'T USE FIREFOX YOU CAN'T EVEN CLICK ON SOMETHING SAFELY!".
You mean like the F/OSS evangelists do everytime a flaw is found in Internet Explorer?
However, I do think there is an important lesson in here - a lot of open source advocates have set an unreasonable level of expectations by proclaiming the amazing magic of open source: A fantasy world where every line is thoroughly vetted by thousands of super-experts, and if the source is available that instantly disproves the existence of malicious intent (put a trojan out, mark in GPL and make the source available, and I'd bet a lot of the converted would immediately download and install blindly. There are countless OSS projects where no one but the author ever bothers looking at the code).
I have to disagree. This sort of exploit is extremely worrying.
At first, Mozilla fans (me included) all said "the chances of Firefox getting 0wned by exploits is very slim, Mozilla is secure by design -- IE isn't".
By about 0.9 or 0.10 the holes started pouring in -- but it was ok: "This is simply Mozilla Foundation's bug patching contest, they are working FOR us instead of AGAINST us."
After this it wasn't only white-hat mozilla funded security experts that started showing there was holes in the code. We changed our story again and, somewhat rightly, pointed out that "these are very theoretical and it would be very hard to use this to exploit a computer like IE can".
This is a really big problem. This will get exploited like crazy as it seems exceptionally easy to do. Not only that, I expect the only fix from Mozilla will be as usual, a 5MB binary installer with the files changed. This is unacceptable on a 56k modem and people just won't bother upgrading to a secure version.
Secunia have already released an advisory explaining how the exploit works:
http://secunia.com/advisories/15292/
This is the first Firefox exploit that has received the rating 'Extremely Critical'.
--- Extract from Secunia's site ---
Description:
Two vulnerabilities have been discovered in Firefox, which can be exploited by malicious people to conduct cross-site scripting attacks and compromise a user's system.
1) The problem is that "IFRAME" JavaScript URLs are not properly protected from being executed in context of another URL in the history list. This can be exploited to execute arbitrary HTML and script code in a user's browser session in context of an arbitrary site.
2) Input passed to the "IconURL" parameter in "InstallTrigger.install()" is not properly verified before being used. This can be exploited to execute arbitrary JavaScript code with escalated privileges via a specially crafted JavaScript URL.
Successful exploitation requires that the site is allowed to install software (default sites are "update.mozilla.org" and "addons.mozilla.org").
A combination of vulnerability 1 and 2 can be exploited to execute arbitrary code.
NOTE: Exploit code is publicly available.
The vulnerabilities have been confirmed in version 1.0.3. Other versions may also be affected.
Solution:
Disable JavaScript.
I'll probably be modded down for this...
For people running Firefox in a business or school with centrally locked down settings I think a quick fix might be to add
lockpref("xpinstall.enabled","false");
xpinstall.enabled seems to be the preference changed by "Allow websites to install software"
The basic problem is that the Mozilla developers, in their futile attempt to create a "platform", put in a mechanism comparable to Active-X - a way to dynamically download executable programs. Of course, they tried to make sure this "feature" could not be used for purposes of evil. Like Microsoft, they failed.
Understand, this isn't subtle. The code uses built-in Mozilla JavaScript extensions to create a local file in a very straightforward way. It then calls "nsILocalFile::launch()" (which does exactly what you think it does) to launch it. Those are capabilities that shouldn't be in a browser's JavaScript engine at all.
Having designed in a potential security hole big enough to drive a semitrailer through, they tried to make it "secure" with the usual crap approaches - signatures, lists of trusted sites, and disabling for certain types of URLs. They failed. They forgot to make those checks for "favicon.ico" files (Mozilla's implementation of a Microsoft icon-in-the-toolbar gimmick.)
Plugging that hole is not the answer. The problem is more fundamental. "nsILocalFile::launch()" needs to be removed. Browsers have no business launching arbitrary executable programs. Period.
In a nutshell, Firefox has the idea that some sites are privileged (namely the sites on the whitelist for installing software), it lets privileged sites have a dangerous degree of control over the user's computer, and it has at least one way for unprivileged sites to execute code in the context of a privileged site.
What are the important differences between this and Microsoft Internet Explorer? In MSIE some sites are in the Trusted Sites or Local Machine zones and therefore privileged. Such sites have a dangerous degree of control over the user's computer, and there have been many ways for unprivileged sites to execute code in the context of a privileged site.
Is Firefox doing something better than IE in its design, or are we going to see a whole class of bugs like this one in the future?
" javascript. The language that has no purpose anymore."
Look into Firefox's chrome directory and say that again.
"Only the small secrets need to be protected. The big ones are kept secret by public incredulity." - Marshall McLuhan
Um, let's take a minute and remember that according to the secunia advisory, ONLY sites that are allowed to install software can exploit this. And by default, that's only update.mozilla.org and addons.mozilla.org. If you are not adding untrustd sites to the list of sites that can install software to your browser, you are probably not in danger. That is not to say this doesn't need to get fixed, it totally does. But we're probably getting a little more excited/worried than there is cause for.
Mozilla provides a number of builds- Windows, MacOS X, and Linux i686, and each in a wide variety of languages.
These are the ONLY builds they should be worried about patching (and if they could make it language independent, it would be 3 packages). Everyone else gets the source code. Let Portage figure out how to update things.