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IE and Firefox Share a Vulnerability
Posted by
kdawson
on Tue Feb 27, 2007 12:51 AM
from the upload-with-daring-and-whimsy dept.
from the upload-with-daring-and-whimsy dept.
hcmtnbiker writes with news of a logic flaw shared by IE 7 and Firefox 2.0. IE 5.01, IE 6, and Firefox 1.5.0.9 are also affected. The flaw was discovered by Michal Zalewski, and is easily demonstrated on IE7 and Firefox. The vulnerability is not platform-specific, but these demonstrations are — they work only on Windows systems. (Microsoft says that IE7 on Vista is not vulnerable.) From the vulnerability description: "In all modern browsers, form fields (used to upload user-specified files to a remote server) enjoy some added protection meant to prevent scripts from arbitrarily choosing local files to be sent, and automatically submitting the form without user knowledge. For example, '.value' parameter cannot be set or changed, and any changes to .type reset the contents of the field... [in this attack] the keyboard input in unrelated locations can be selectively geared toward input fields by the attacker."
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IE and Firefox Share a Vulnerability
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Awww, that's so cute (Score:5, Funny)
Nope (Score:4, Informative)
(http://members.cox.net/bungi/)
Re:Nope (Score:5, Interesting)
(Last Journal: Saturday January 06 2007, @01:13AM)
I'm not too worried about it, because in my office I use Linux and I run WinXP in a virtual machine, in that VM I use a nonadmin account for normal stuff - viewing and priting Word or Excel docs, instant messaging, AND I use the Run As feature to launch browser windows as yet another different nonadmin account. On the Linux host itself, I run firefox as a different user from my main user account.
So if I gather correctly, you can grab my bookmarks or downloaded files, IF I actually type all the letters to those specific paths? That's it?
I'd be more worried about Windows graphic driver exploits - graphics drivers seem a bit shoddy- plus they are all about performance, not security. And currently it's basically - Nvidia, ATI and Intel.
I've had weird things happen with Linux sound though so I wonder about the security of such stuff. I've pretty much given up on getting Linux sound to work properly for sustained periods of time (this on suse 10.0, perhaps I should try 10.2).
Re:Nope (Score:4, Insightful)
(Last Journal: Saturday January 06 2007, @01:13AM)
If you use the same user account for work, ssh and browsing then you risk exposing stuff like:
~/.ssh/id_dsa
~/.ssh/id_rsa
Which in some cases might be more interesting than
How it works (Score:3, Insightful)
Is the way this works by attaching keydown/keyup events to the document object, and then switching focus to the file upload field in order to let the user fill in the upload? Ingenious :)
So a browser would fix this by not allowing programmatic access to focus() for file uploads?
It doesn't sound like this would be particularly exploitable because you'd need them to type the letters in the right order (with other arbitrary letters as padding between this). Getting someone to type something might prove easier though now due to the prevalence of Capchas.
Re:How it works (Score:5, Insightful)
(http://marcrust.blogspot.com/)
You took the words right out of my keyboard, no pun intended*.
It won't affect my commenting on blogs or sites that I normally frequent. But after that demo, I admit I probably won't look at captchas the same way again.
* OK maybe one quick pun.
Offtopic (Score:1, Offtopic)
The real common vulnerability... (Score:3, Funny)
(Last Journal: Saturday December 09 2006, @10:46PM)
For good or ill, I don't know many regular users, of course it is lonely at times...
Doesn't work with Firefox 2.0.0.1 on Windows XP (Score:4, Informative)
Also, there is no need to type all that jibberish about cheese. Just slowly type in:
C:\boot.ini
Type it too quick, and the javascript in the background won't be able to keep up with the rate of keystrokes you enter.
Vulnerability doesn't work on Vista (Sort of) (Score:2, Interesting)
I had to create a Boot.ini file in my C: drive since Vista doesn't have it there anymore. IE7 and Firefox will be able to pull information out of the file if you have permissions to read the file but if you don't it won't work. This is probably why some people are reporting it doesn't work in Win XP with a user account. Only admin accounts are affected because the user accounts probably don't have read access for boot.ini.
This means that the vulnerability won't be able to access any system files but it could potentially access sensitive data you have because you'd obviously have permissions to read those files (i.e. Word documents on your desktop).
It seems that the person using this exploit would have to know the exact filename and path of the file he wants so this seems like a minor issue. The real risk is with system files because the directory and filenames for those will most likely be the same on most systems but those can't be read and I'm not sure what you'd do with the info anyway...
Try as I might... (Score:2, Interesting)
(http://obscenely.strangled.net/)
Works on FireFox under Linux (Score:5, Interesting)
http://www.thanhngan.org/fflinuxversion.html [thanhngan.org]
Sad realization (Score:2, Funny)
How does that even count? (Score:1)
(http://www.segfault.gr/)
C:\ is my boot drive. (Score:1)
(http://www.chrisllorca.com/)
I wonder how quickly this may become a real threat in the wild and how quickly the manufacturers can patch it...
Perhaps... (Score:1)
Anyone else try Opera ? (Score:3, Insightful)
Windows XP
As Administrator
With No 3rd party anti-virus or anti-spyware protection whatsoever (total of 20 processes running including Opera)
Opera 9.10
All scripting enabled
Checked the presense of boot.ini
And while it did continue to a new page when I typed the phrase, that new page didn't have the contents of my boot.ini file.
Just a message telling me what that page was about.
They already share a vulnarability... (Score:2, Insightful)
(http://www.temmink.org/)
Firefox 2.0.0.2 + IE6 (Score:1)
(http://www.tssci-security.com/)
Below should be a copy of your C:\BOOT.INI file. If nothing is
shown, chances are you don't have this file in the first place,
your account has no permission to read that file, you didn't use
a vulnerable browser, or I screwed something up.
=== RECEIVED DATA ===
[boot loader]
timeout=30
default=multi(0)disk(0)rdisk(0)partition(1)\WINDO
[operating systems]
multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Micr
Requires javascript (Score:3, Informative)
New/unknown sites won't be able to do this, but my previously "trusted" ones will.
Possible workaround (Score:1)
(Last Journal: Sunday November 20 2005, @03:55AM)
The Firefox demo also is sensitive to the typing speed, for example, if you type "bnoot" instead of "boot" and you type the "n" very quickly after the "b" the demo tries to open the C:\bnoot.ini file instead.
Variation on an old bug (Score:5, Informative)
(http://www.squarefree.com/ | Last Journal: Saturday August 09 2003, @09:27PM)
Zalewski's version is bug 370092, and he was unhappy when I marked it as a duplicate of bug 56236.
What about Konqueror? Or Safari? Or Opera? (Score:4, Interesting)
(Last Journal: Thursday November 03 2005, @08:42PM)
The vulnerability is called 'users' (Score:2)
(http://www.cgisecurity.com/)
And the workaround is... (Score:2)
I thought this was fixed ? (Score:2)
(http://www.dvstocklocker.com/ | Last Journal: Wednesday October 20 2004, @06:21PM)
The Reg [theregister.co.uk] carried this story yesterday. I don't know if IE7 is fixed yet, but I had an auto update to Firefox (2.0.0.2), 3 days ago.
Doesn't work here (Score:1)
(http://ermarian.net/)
It does catch the first "c" I type, but it stops after that - colons aren't caught.
Two theories:
1 - One of my numerous Firefox extensions is interfering with the Javascript
2 - I'm using a German "kezboard". Colons are in a different place. Now off to check if my uppercase "Ö" gets captured...
it's a POC (Score:2)
It's a proof of concept about a focus redirect exploit (bug? that's a misnomar). The example itself (displaying boot.ini) is not the exploit, the exploit is the hijacking of selective typed text in one textbox and applying it to another. The application of this exploit could be much different than displayed in this example.
NoScript stops it (Score:2)
(Last Journal: Wednesday October 31, @08:33AM)
Wrap it up! (Score:2)
(http://www.loconet.ca/)
The race is on! (Score:2)
IE7, Firefox2, Opera9, Konqueror and Safari (Score:2)
Of Course They Do! (Score:1)
IP violation (Score:2, Funny)
(http://www.grandrapids-lug.org/)
With all these FireFox vulnerabilities... (Score:2)
Minefield (Score:1)
(http://www.theqcp.org/)
Detection seems a bit random (Score:1)
wtf? (Score:2)
The real problem lies in that it is there, just not visible in the browser.
I can accept that. The key is style="position: absolute; left: -500px;...
And then the div tag's style: style="position: absolute; left: 510px;... that takes the form and puts it back to pop
Then the dev closes the div tag and places the file field to the left.
Clever. But there is some security in obscurity. Knowing which files to grab that are of real use... I suppose grabbing someone's registry could yield something interesting about the user, and then parsing through it to find relevant keys and then using another form to get something of real value would be about the most useful thing you can do...
I think it's really sweet (Score:2)
Hack of a Work-Around (Score:1)
(http://www.pitt.edu/~zld1/)
I've used it for years! (Score:2)
(http://the-junkyard.net/)
I don't really see how this is an "exploit," since it seems to require user intervention. But in any case, I've been doing this using VBA with IE to automatically fill out file upload fields - for years.
I know, I should have used Curl or something back then, but it was Access VBA. Don't blame me!
The real "fix," though, would be to remove the text box entirely and just have a browse button.
Really Needs a Proper Fix (Score:1)
Maybe we can finally dispense with the whole clunky two-step file upload. I mean who ever actually types a file name into the file upload field. You press the browse button to populate the field and then hit submit. Smart sites actually script it to one step by doing a submit off an onchange event in the file field. There really is no need to ever present a field to start with and it is just an accident waiting to happen. The upload should be one step that cannot be "messed" with.
Re:IE7 Vista (Score:2, Interesting)
(http://holloway.co.nz/)
If so then it's still vulnerable because they'll release a patch to stop hackers from uploading user files, like those with predictable filenames. It seems wrong to say that IE+Vista aren't vulnerable when the IE bug still exists.
(of course if IE7 prevents giving focus to the upload field then I'm wrong -- but I don't think that's the case. The same bug exists in IE7 on Vista)
Re:IE7 Vista (Score:2)
From what TFA says though, protected mode protects IE on Vista.
Re:IE7 Vista (Score:5, Informative)
Re:IE7 Vista (Score:5, Insightful)
The latest Web 2.0 Captcha:
C:\ W IN D O W S\ sys tem 32\config\S AMYou heard it here first!
Re:innerHTML (Score:2)
(Last Journal: Tuesday October 30, @10:59AM)
Re:Offtopic rant (Score:2)
This is patently false. This conversation is very nice, so I'm going to go and play a gay game, get a cool drink, watch a counterfeit video and get some truly bad snack food.
Re:Offtopic rant (Score:5, Informative)
Seeing this in tech news just shows how much this has spread. I no longer want to use the word enjoy at all because every time I hear it, I am reminded of this usage and feel a twinge of annoyance.
I want my English language back from these idiots!
You'll have to go a long way back to claim this one.
Re:Offtopic rant (Score:2)
(Last Journal: Sunday November 06 2005, @05:24PM)
You have to realize how ridiculous these people are. They babble for a living.
I must warn you that I have heard marketing people talking about their "Spider Sense tingling" and needing to "ping" colleagues for information.
"Your language" has been and always will be hostage to idiots. If you want to feel more secure, I suggest that you change your language from English to C. The C compiler is much stricter.