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MSN, Word Vulnerable To Shell: URI Exploit
LnxAddct writes "InfoWorld is reporting that a few Microsoft products are also vulnerable to the "shell:" scheme vulnerability found in Mozilla last week. These applications include Microsoft Word and MSN Messenger."
Comment removed based on user account deletion
Mac OS X' Safari had a very similar flaw, where one could use disk:// to mount a disk image, which could execute whatever it wanted to.
That flaw was fixed with the 2004-06-07 security update.
According to newsforge, it took "barely a day" for Mozilla to release new builds and patches.
The URI exploit in its general form is mitigated by the fact that you can't pass any command-line arguments to the command. So you can launch a bunch of Notepads, so what? However, you CAN type a filename in and have it open in its associated application. If that filename is too long, you can exploit a buffer overflow in the helper application. There happens to be a plentitude of client applications on a standard XP box with buffer overflow possibilities. Once you're there, go anywhere you want with the privileges of the user on the XP box (which is usually admin, and if not, you can usually get admin without a lot of effort).
Anyway, SP2's memory protection would have prevented the overflow attack. It would not have prevented the most general (and less harmful) form of the attack, however.
What the original poster was probably meaning, if he had a point at all, was that non-Windows systems don't do this sort of "command-line-as-a-protocol" bullshit because it's quite obviously the wrong way to do things. Security through obscurity works in a lot of cases because people think "nobody would EVER design an OS that did THIS" and they never bother to look. Well, now someone's looked and found an ancient kludge coded by someone who probably doesn't even work for MS anymore. And more man-hours are going into fixing this bug than would have gone into creating a proper implementation of whatever this goober was trying to accomplish in the first place.
That said, Open Source isn't pixie dust that makes everything happy and secure. Stupid things happen in Linux. They just happen in the open where people can find them and fix them before applications start relying on them to function.
Actually, it was their source that was the root of the problem in the first place. The whole "shell" thing is only in windows, unfortunately the article titles lead people to believe that it is a problem with Mozilla across all platforms, when in reality it only affects those running on a Windows platform.
(that subject is a great way to get modded down)
I created a shell link inside Office Word 2003 and when I clicked it I was warned that the hyperlink contained a potentially dangerous target and that I should only proceed if I trusted the source of the document. This warning does not appear for http, https, ftp, or other common "safe" protocols.
I do not have MSN available for testing.
http://brandonbloom.name
The Article's title is: Microsoft products also vulnerable to Mozilla flaw That is gross misinfomation, it should be something along the lines of "Microsoft products allow exploit of OS flaw, similar to Mozilla." The flaw itself is in the Windows operating system. It exposes access to shell functions that applications need to blacklist. Application developers shouldn't need to be concerned with "Oh, I need to stop that protocol for security." It should be the protocol developer's responsibility to say "Is this safe?"
Yet another signature that refers to itself. The irony and humor is dead.
Microsoft Word 2003 w/Latest Updates.
Insert > Hyperlink
shell:explorer.exe (path should be unneccessary, tried shell:windows\explorer.exe as well)
Critical Error Dialog pops up
Opening "shell:explorer.exe"
Hyperlinks can be harmful to your computer and data. To protect your computer, click only those hyperlinks from trusted sources. Do you want to continue?
Yes | No
Pressed Yes and nothing to happened.
The title is quite misleading on first glance.
"Microsoft products also vulnerable to Mozilla flaw"
If it was a Mozilla flaw to start with, my linux boxes would be vulnerable. I know its picky, but the title is not accurate IMHO as Mozilla is being used to take advantage of a Windows feature, rather than the flaw itself existing in Mozilla.
It seems logical that the solution to many of these browser exploits is to run the browser with a separate set of OS permissions, i.e. as a separate user. This could be done using setuid under Unix. I don't know how it's accomplished on Windows.
The special user would have greatly reduced permissions, which would prevent these exploits from being useful. This user could not execute anything but designated plugins, and could not save files except to a designated area.
Why has this not been tried?
To try out open source browsers like Firefox and Mozilla....
;)
;)
Maybe its about time for some people to concider some alternate producivity suites - not just openoffice - even some suites like Corel have some intriguing software that lacks the user base of microsoft.
Rant>./rant
On a sidenote.. Corel lost a big share of its market to MS Office around the same time Netscape was crushed by IE. I remember my highschool used Corel at the time. Netscape was very smart to start the Mozilla Foundation insead of trying to beat MS, they are letting their supporters promote for them, gaining them some brand awareness if nothing else. Perhaps It wouldn't be so strange if Corel was to support a open source initiative, or merge with OpenOffice. The next best thing since frozen coffee for the computer geeks would be firefox and corel. Corel could sure use some geek to geek praising around now
For those of you not very firmiliar with Corel, at one point they were doing fairly well, then they kinda fell thru - had to lay off alot of people and are now trying to get back into the market.. but I personally think they face the same fate as Netscape.
In the real world, If you loose a customer, it takes twice as long to get that customer to come back to your business, and that customer is a big factor keeping other possible business from you, as they will tell at least 10 people of their experiance.
Based on this, even old Corel users would be hesitant or unwilling to switch back to Corel -so Corel needs a new movement. Open source anyone
Dying Proprietary Software + Open Source = Improved Code + Brand Awareness + "PROFIT" (Donations, Memberships? Support? and Smart Usage Of Your Brand Recognition)
With so many software companies expected to bust with news of the markets this week, I wouldn't be surprised to see a few new related open source projects pop up.
Rant> logout
Mod me down im a newf (wiki)
Okay, I'll bite. Some of us have a standard of stability and completeness, totally independent of version numbers. Was Internet Explorer 1.0 a happy, complete, stable application? Is Firefox 0.9.1? I think you're fooling yourself if you think version numbers provide any sort of yardstick of the readiness-to-use of an application. I personally won't use ANY Microsoft product in a production (read: at work) environment until it has at least TWO service packs. Windows, Office, SQL, SMS, doesn't matter. Microsoft's standard is "it's 1.0 when we need to release it. it's sp2 when it's ready for prime time". Not all companies are the same way. Corel has yet to release a product ready for prime time, and WordPerfect's up to 12 or so. Cisco, when motivated, can get things done right in the first release. Open Source projects all have their own standards. Firefox 0.9.1 is much more mature and ready for prime-time than the latest PR or SP2. The Xine maintainers, who must all be insane,
have a project that's been stable for years and it hasn't hit 1.0 yet. If Firefox suddenly released 2.0 would it sudenly be more mature? How about 3.0? What's the magic happy number? THERE IS NONE. You have to gauge each vendor, and each application, by a consistent set of rules and just forget what version number the marketing people decided it should have.
Here'show it works:
You predict the next security flaw,exploit etc etc etc and what product it will hit. Apache buffer overflow (smart money says don't pick that one), Word vulernability etc. This could be cool.
Dibs on Wednesday IE exploit.
I boycott signatures
There is a big difference between the degree of risk I take with upgrading Firefox and the major overhaul that SP2 is going to turn out being. Sorry but this hypocrite isn't buying your assertion.
I don't want knowledge. I want certainty. - Law, David Bowie
I did not contact Microsoft before posting on Full Disclosure. I thought posting to Full Disclosure would encourage Microsoft to fix the hole in Windows rather than forcing every software vendor to work around it using a whitelist or blacklist. Maybe I was wrong about that. I felt that all software vendors should be given an equal chance to fix the hole if they want to be safe running on unpatched versions of Windows. I was frustrated that Mozilla looked bad because of a Windows hole that affected a large number fof programs.
I got an IM from someone at Microsoft thanking me for the post on Full Disclosure. Microsoft earned a little respect from me today.
The shareholder is always right.
emacs will hit version 1.0 when it can shake the programmer's hand, look him in the eye and say "I'm ready."
That's becaues it's NOT a bug in mozilla, it's a massive security hole in Windows. Mozilla finally decided to patch it for mozilla because MS was too damned lazy to fix it. As we now see, this massive windows hole affects other products too. Of course, NO other platform has this particular security hole (surprise surprise...)
If your flash plugin had a security hole, would you expect Mozilla, Opera, IE, etc to filter certain access so that security hole could't be exploited?
No, MS is responsible for the security of their own products.