Blog Entries - Technical

Dexcode Teardown of the Android SMS Trojan

August 10th, 2010

I got my hands on a copy of the recent Android SMS trojan that commits toll fraud via SMS messages to premium Russian shortcodes.  What follows is a brief teardown of the APK and disassembly of the trojan’s dexcode and description of its malicious functionality.  It’s incredibly simple in nature so there’s not much detail to go into.

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A Peek Inside the GTalkService Connection

June 28th, 2010

This posts aims to peek inside the Android GTalkService connection and observe its protocol.  In particular, we’re interested in the INSTALL_ASSET message and whether or not it is protected by any additional cryptographic signatures beyond the intended guarantees provided by the SSL transport.

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Remote Kill and Install on Google Android

June 25th, 2010

In this post, I’ll talk about the REMOVE_ASSET and INSTALL_ASSET mechanisms that can be invoked by Google via Android’s GTalkService to not only remotely remove applications from an Android device but also remotely install new applications.

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SummerCon 2010 Slides

June 21st, 2010

SummerCon was absurdly fun.  Thanks for redpantz for putting on a great event and all the NY guys for making it a blast.  My talk was on a few random Android topics…slides are available below.  I threw everything together about 12 hours before my talk so it’s a little rough around the edges and a few slides have been redacted for now.

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SOURCE Boston Slides

April 25th, 2010

Just got back from SOURCE Boston.  SOURCE was a great event: a great line-up of speakers, fun social events (thanks to Rapid7 and iSEC for sponsoring), and smooth execution (props to Stacy and Zach).  My talk was on the topic of Linux kernel security, slides are available here.

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ReiserFS .reiserfs_priv Vulnerability

April 10th, 2010

A vulnerability in the ReiserFS filesystem of the Linux kernel (versions <= 2.6.34-rc3) allows for the unprivileged reading and writing of objects in the .reiserfs_priv path.  Leveraging extended attributes and POSIX file-based capabilities, this vulnerability allows for privilege escalation on systems with a ReiserFS filesystem.

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Mirrors of MoKB and MoAB

March 15th, 2010

Wow, it’s been forever since I’ve written any entries…startup life is busy, but fun!  Nothing interesting in this one, but I thought I’d post for Google purposes that I’ve mirrored copies of the Month of Kernel Bugs (MoKB) and the Month of Apple Bugs (MoAB).

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Linux Kernel x86-64 Register Leak

October 4th, 2009

A recent vulnerability in the Linux kernel (versions <= 2.6.32-rc1) allows the leakage of certain register contents.   The x86-64 registers r8-r11 may be leaked to 32-bit unprivileged userspace applications that switch themselves into 64-bit mode.

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Disabling Green Dam with Dam Burst

September 28th, 2009

Dam Burst is a simple utility that allows an unprivileged user to disable the censorship functionality of the Green Dam Youth Escort software.

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Hostage Taking Botnets

September 11th, 2009

What happens when a botnet operator decides to hold infected machines hostage and announces demands?  What organization is in charge of cyber-related hostage situations? What are the trade-offs of giving in to the demands?

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