OSEC

Neohapsis is currently accepting applications for employment. For more information, please visit our website www.neohapsis.com or email hr@neohapsis.com
Re: [Full-disclosure] Exploiting memory corruption vulnerabilities on Internet Explorer 8

From: Jared DeMott (jared.demottharris.com)
Date: Thu Oct 01 2009 - 10:27:22 CDT


Freddie Vicious wrote:
> Microsoft has released Internet Explorer 8 on March 19, 2009 and up to
> now there's no reliable method to exploit memory corruption
> vulnerabilities on it?
>
> I mean, on IE6 and IE7 we had SkyLined heap spray technique, first
> seen in the IFRAME overflow exploit [1] which have been used by almost
> every IE memory corruption exploit so far. Internet Explorer 8 was
> enhanced with DEP and ASLR protections, making heap spray useless.
> Then Mark Dowd and Alexander Sotirov published their great paper -
> Bypassing Browser Memory Protections [2] providing some excellent
> techniques, mainly the .NET binary technique which bypasses DEP and
> ASLR which was used by Nils on the latest Pwn2Own to own Internet
> Explorer 8 RC (Release Candidate) [3] and was used to mass-exploit
> other vulnerabilities [4]. One day after Nils owned IE8RC, Microsoft
> released Internet Explorer 8 RTM and blocked the option to load .NET
> DLLís from Internet zone and Restricted sites zone. Due to the fact
> that most of IE exploitation doesnít occur in Intranet/Trusted
> sites/Local machine zone, this makes the .NET DLL technique irrelevant
> most of the times.
> So my question is - Is there no reliable method to exploit memory
> corruption vulnerabilities in Internet Explorer 8?
I'm not aware of any catch-all technique just for IE8, though there are
a few common ones like return oriented programming. Application
specific techniques are also common when third party extensions are
involved.
>
>
> [1] http://milw0rm.com/exploits/612
> [2] http://taossa.com/archive/bh08sotirovdowd.pdf
> [3]
> http://dvlabs.tippingpoint.com/blog/2009/03/18/pwn2own-2009-day-1---safari-internet-explorer-and-firefox-taken-down-by-four-zero-day-exploits
> [4] http://milw0rm.com/exploits/8969
>
> --
> Best wishes,
> Freddie Vicious
>

--
__________________________________________
Jared D. DeMott
Principal Security Researcher

_______________________________________________
Full-Disclosure - We believe in it.
Charter: http://lists.grok.org.uk/full-disclosure-charter.html
Hosted and sponsored by Secunia - http://secunia.com/