Metasploit Gets Covert Forensics And PXE Boot Attack Capabilities

Black Hat USA and DefCon bring a wealth of knowledge, new tools, and updates to old favorites. One thing that is often disappointing is that tools are released and nothing ever happens to further development. I attended several Metasploit-related talks, but I think it was during HD Moore's talk at BSides Las Vegas where I heard it said that if it makes it into Metasploit, it has to be maintained. That's great news because there have been some awesome, independently developed Metasploit modules released in Vegas that have since been included within the Metasploit Framework.

There were three presentations that included the release of Metasploit modules that I was particularly interested in. I've written about one of them, vSploit, before, so I'll just point to the previous post here. The other two were "Covert Post-Exploitation Forensics With Metasploit" and "Network Nightmare: Ruling The Nightlife Between Shutdown And Boot With PXEsploit."

The first was a presentation by Wesley McGrew (slides and code here) on leveraging Metasploit for covert forensic work once a system has been compromised and is running the Metasploit Meterpreter payload. Wes wrote three post-exploit modules designed to enumerate the drives on a remote Windows system, image a drive, and mount a hard drive over the network in a read-only state to run forensic tools against.

There are a slew of possibilities from both a penetration tester's and a forensic investigator's perspective. Need to determine covertly whether a file is or was on a hard drive? Deploy Meterpreter via the psexec module and go digging using standard forensic tools like the Sleuthkit, FTK, or EnCase. Similarly, start digging for deleted files that might contain passwords or sensitive data that is normally encrypted but decrypted on the filesystem when opened.

The other presentation that I was really excited to see was from Matt "scriptjunkie" Weeks on his PXEsploit modules (slides and demos heres). PXEsploit takes advantage of computer systems (i.e., desktops, servers, laptops) with PXE booting enabled. PXE is great for deploying operating systems over the network, but it's also great for owning unsuspecting organizations as Matt has shown with his new modules.

One of the things that I really like about Matt's work is that it is not limited to attacks where you have only local network access as one might expect. He has written one module to handle the attack if you're sitting in your target's network, and he has also written another that is a post-exploit module that runs through a compromised system running Meterpeter. Imagine owning one computer through a social engineering attack using a client-side exploit only to pivot through and own the rest of the network using PXEsploit.

All of the modules mentioned above are in the Metasploit Framework, so run "msfupdate" or "svn update" to make sure you have them. I definitely recommend testing them and seeing how they might fit into your testing. If you're a defender, then it's a good idea to look so you can better defend against them.

In case you've never used Metasploit or have limited experience with it, I highly recommend the No Starch Press book "Metasploit: The Penetration Tester's Guide." It's a great book to get people started, has examples to walk through, and includes more advanced topics for experienced users.

John Sawyer is a Senior Security Analyst with InGuardians. The views and opinions expressed in this blog are his own and do not represent the views and opinions of his employer. He can be reached at [email protected].