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New Method Could Hide Malware In PDFs, No Further Exploits Needed
Trailrunner7 writes "A security researcher has managed to create a proof-of-concept PDF file that executes an embedded executable without exploiting any other security vulnerabilities. The PDF hack, when combined with clever social engineering techniques, could potentially allow code execution attacks if a user simply opens a rigged PDF file. With Adobe Reader, the only thing preventing execution is a warning. Disabling JavaScript will not prevent this."
That fact made me uninstall Foxit for now at least.
You shouldn't have to wait long.
http://forums.foxitsoftware.com/showthread.php?t=18029
this issue has been confirmed, and a maintenance version will be released within this week.
"Our two-party system is like a bowl of shit looking at itself in a mirror." - Lewis Black
From the author:
" My PoC PDF requires some changes for Foxit Reader, because ultimately, the executable doesn't run. But that's probably due to some variation in the PDF language supported by Foxit Reader."
Not really a proof of concept since the proof doesn't actually run the code currently. Not that it couldn't but there's no proof that Foxit is less secure since it doesn't actually run the code.
) Human Kind Vs Human Creation
) It'd be interesting to see how many humans would survive to serve us.
http://blog.didierstevens.com/2010/03/31/escape-from-foxit-reader/
He got it working in Foxit pretty quickly after the first post about the PoC.
I was reading a technical forum (used by a few dozen people, I'm in a niche market) with Chrome, when a PDF popped up containing nonsense text.
Ofcourse I wasn't happy about it, so I contacted the owner of the site and scanned my laptop with McAfee's antivirus. Didn't find anything, but 2 weeks later I received a mail that my passwords had been reset for my own website because of suspicious activity. As it turned out, someone had installed a virus similar to the one that got me, on my contact page. Great.
This is with a laptop running Chrome, Windows Vista with UAC enabled, McAfee security suite. I didn't even get a warning.
I used Malwarebytes' Anti-malware to find and remove the stuff that got installed. At least, I'm hoping it got removed - but nothing is certain :P The strange thing is now, that when i need to access a fishy site I use Internet Explorer because it caught the drive-by download the next time I visited. Sort of a complete reversal of policy for me.
Therefore, by the (faulty) logic you're using, you're just a cow with a keyboard - osu-neko (2604)
Also the first comment there says how you can hex edit the .exe to disable this "feature".
If you can live without the /Launch functionality (I can!), edit the executable:
- search for “^@Launch^@” (^@ == null byte, file offset 7040965 in 3.13.1030) in Foxit Reader.exe,
- change it to e.g. “L!unch” (no quotes),
- save AS BINARY,
done.
Comment by Thomas — Wednesday 31 March 2010 @ 12:20
Someone came up with a better test file, here:
http://seclabs.org/fred/docs/sstic09/samples/actions/launch/calc.pdf
The first test file contained code essentially saying "if you're on a windows box, run cmd.exe". This one says "if you're on windows, run calc.exe, and if you're on Unix, run xcalc, and if you're on MacOS, run Calculator.app". So regardless of platform, if you load this PDF and see a calculator come up, well, you've learned something.
As it happens, the PDF also contains real content that describes expected behaviors with a couple of readers. Apple's "Preview" isn't vulnerable because it doesn't implement the /Launch command at all! But Adobe's reader on MacOS is vulnerable.
Ever since Adobe perfected the basic PDF functionality and needed to keep adding features. Whether they are frills or not, whether they depart from the purpose of PDF or not, Adobe has to do this to justify its marketing. They want their customers to have reasons to keep wanting the latest version. Feature creep, in other words.
It is a miracle that curiosity survives formal education. - Einstein
It can, although it doesn't mean that Mac and Linux are just as vulnerable as Windows.
If you download this proof of concept which works on Linux, Windows and Mac:
http://seclabs.org/fred/docs/sstic09/samples/actions/launch/calc.pdf
you'll discover that although it works in Acrobat Reader on the Mac, the Mac Preview application, which I would hazard is used to open the vast majority of PDFs on Macs, does not support /Launch and thus isn't vulnerable to the attack.