Setiri + Invisible browsers != browsers

[Haroon Meer <haroon () sensepost com>]

Hi..

About 2 years ago, we demo'd Setiri, a win32 trojan that tunneled data 
off networks through the use of Invisible Internet Explorer instances. 
This allowed us to avoid sticky issues like authentication / etc and 
worked nicely against personal firewalls configured to allow out IE traffic.

 Despite the noise it generated back then, very little has been done to 
combat the problem. So we threw together a few lines of C# and tacked on 
a  gratuitous .pdf (for good measure) for an angle we believe can go a 
long way towards mitigating the threat..

In short : an invisible browser is not the same as a visible one, and 
personal firewalls (that do outbound application control) should not 
treat them the same. Application-level access control systems should be 
able to detect whether an application is running visible or not.

The short paper : http://www.sensepost.com/garage_portal.html / 
http://www.sensepost.com/restricted/casper.pdf

The badly written C# : http://www.sensepost.com/garage_portal.html / 
http://www.sensepost.com/restricted/casper.zip

As usual, please mail questions/comments/flames to 
research () sensepost com / haroon () sensepost com

/MH

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Haroon Meer                                                         MH
SensePost Information Security                          +27 83786 6637
PGP : http://www.sensepost.com/pgp/haroon.txt     haroon () sensepost com
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