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New Remote Flaw In 64-Bit Windows 7
Trailrunner7 writes "Researchers are warning about a new remotely exploitable vulnerability in 64-bit Windows 7 that can be used by an attacker to run arbitrary code on a vulnerable machine. The bug was first reported a couple of days ago by an independent researcher and confirmed by Secunia. In a message on Twitter, a researcher named w3bd3vil said that he had found a method for exploiting the vulnerability by simply feeding an iframe with an overly large height to Safari. The exploit gives the attacker the ability to run arbitrary code on the victim's machine."
Watch out!
SJW: Someone who has run out of real oppression, and has to fake it.
So far you must use Safari under Win7 64bit to exploit this. But we would never want to say anything bad about Apple, only about Microsoft...
http://www.h-online.com/security/news/item/Highly-critical-zero-day-vulnerability-in-Windows-discovered-1398625.html
Uh, Linux geek since 1999.
Safari runs on Windows? Any time I've tried running Apple software (iTunes, Safari, Quicktime) on Windows, it just takes forever to load, wants to spend all day updating, chews up my memory and craps on my processor. If someone is running Safari on Windows intentionally then they might be masochistic enough to welcome this 'feature'
TFA suggests it allows kernel privileges, so it is certainly a Windows exploit. But it may also be a Safari bug too, it depends whether or not the data it is passing to the Windows API calls that are causing the exploit would be considered reasonable or not.
Remote to me means "it's connected, you're vulnerable". This requires the user to take an action, getting some local data. From the description, you could have the same files on the file system and it would work.
Bad? Yeah. But not "plug it in, computer is pwned" bad.
The flaw seems to be in a call to a Windows API.
It is possible to trigger a memory error in the system file win32k.sys by accessing a crafted HTML file in Safari....According to webDEViL, the source of the vulnerability is the function NtGdiDrawStream.
So it is possible other programs could be affected. It is also possible that Safari itself handles the function in a broken manner. Note that Firefox appears to also have crashes related to that function (on x86 Windows, though, it's like the second Google result for that function). So, really impossible to say at this point. Also, they could only cause Windows to crash, not to run arbitrary code or anything. So far anyways.
"None can love freedom heartily, but good men; the rest love not freedom, but license." --John Milton
Addendum: <iframe height='18082563'></iframe> causes a BSoD by the Windows kernel so it is certainly a Windows bug. It would be trivial of Apple to hotfix it to prevent exploitation via Safari but any other application could theoretically exploit it and elevate their code. Of course it doesn't appear anyone else has actually gotten it to execute arbitrary code yet, despite the summary claim...
Missing the point. Point is that userland code (and the example uses Safari but what should it matter *what* program activates it - it shouldn't be possible and can probably be easily activated by any sort of direct code) creates a BSOD in Windows.
That shouldn't happen - that's the whole point of an OS.
(check one)
[ ] Microsoft products are far less secure than Apple. Because everyone knows that Safari is completely safe always on Apple machines, and only fails on Windows.
[ ] Apple products are far less secure than Microsoft. Because obviously the hole in Microsoft security here is introduced through an Apple product, and really doesn't occur otherwise.
[ ] If people were just running Linux, they wouldn't be having these problems.
[ ] This is gonna be good. Ima gettin' my popcorn now!
Check your premises.
After a bit bit of playing "let's intentionally crash Windows", it seems that using the Windows Classic skin fixes the bug, and the page renders fine (if a little uninteresting, it's basically a long page with a box on it). It BSODs on Windows Basic and Aero. I haven't a clue if this is a real fix, or if it's just that the magic number needed to crash the system is different with Windows Classic compared with Basic / Aero. Windows XP (32 bit) is fine as well (again page renders fine, no crashes of anything).
I personally think it's largely a Windows bug, even if Safari has a bug (that oddly only does anything on one version of Windows, and even then only with certain conditions), a programme doing something stupid should not crash the entire OS.
10 PRINT "LOOK AROUND YOU ";
20 GOTO 10
For now it's unclear how bad is this, as the only concrete detail is Secunia's link to "original advisory"
From digging around bug submitter's twitter:
@igursev @therealsaumil not really an integer overflow. Otherwise 18082564 would have also worked ;-)
4 hours ago
w3bd3vil webDEViL @
@igursev It probably is, but not theoretically. In simpler terms, I can't build an exploit for it.
12 hours ago
@kernelpool yeah I tried with some help to get code execution but was beyond me...
19 Dec
@r3dsm0k3 Yeah. It's the NtGdiDrawStream which is being called multiple times...leading to a not so interesting crash.
18 Dec
<iframe height='18082563'></iframe> causes a BSoD on win 7 x64 via Safari. Lol!
18 Dec
So a) there's a bug in win32k.sys, tickled by Safari's (allegedly) incorrect API usage, so there's possibility of other exploits, b) "may lead to arbitrary code execution" means "we don't know yet, but we're playing safe", the only confirmed effect is BSoD by memory corruption.
Why the fuck there's so little about it, did nobody research yet what kind of memory corruption it actually does? The tweet's from 4 days ago, FFS.