Virtual Machines for Security

k-hell writes "Researchers from the University of Michigan are using virtual machines to 'to provide security in an operating-system-independent manner.' They have designed and implemented a replay service for virtual machines called ReVirt, which 'logs enough information to replay a long-term execution of a virtual machine instruction-by-instruction.' A system called BackTracker 'automatically identifies potential sequences of steps that occurred in an intrusion,' and they provide a nice example of BackTracker's output for an attack against a machine that they set up as a honeypot, where an attacker gained access through httpd. Here's the source code."

Comments

Re:Operating System Independence?

[dki]

Not to nitpick, but they don't use User Mode Linux. They use UMLinux, which differs from the former in that in UMLinux the VM is contained in a single host process, whereas in User Mode Linux each guest app has its own process. The confusion comes in because UMLinux is considered a type of User Mode Linux, hence the name. Confusing enough?

Re:Hmm..

[martyros]

Putting security services in VMs has been done for years.

The particular service we're providing, ReVirt, is new to Virtual Machines (as far as we know). We don't log normal "security" information, like login attemps, etc. We log just enough information to be able to roll the virtual machine back to a previous state, and make it execute exactly the same way.

One of the (many) problems with security logs is that you frequently don't know everything that you really need to log until after the fact. With our system, you can go back and find out anything you want to know, because you have a live VM doing exactly what it did during the attack.

BTW, the technique we're using for ReVirt was described back in the late 80's, and implemented in the mid 90's for debugging purposes; we're the first ones, as far as we know, to put it in a (somewhat) general-purpose virtual machine, like UMLinux.