Gl.ib.ly

Over at the Honeynet Project they used to run security competitions which were quite a bit of fun. I remembered one in particular which I looked at but hadn't completed. It dealt with the forensic investigation of a floppy disk. I was tinkering with an application to measure byte entropy and thinking of a way that it could be used in a forensic investigation. There is no point using the little application to analyse my terabyte (TB) sized drives so remembering the floppy disk challenge I downloaded the floppy disk image (1.44MB;MD5 = b676147f63923e1f428131d59b1d6a72).

Continue reading "Analysing the byte entropy of a FAT formatted disk"

Today I am adding a malicious system call to the Linux kernel which will allow the caller to do something they cannot normally do in user mode. When attacking a Linux box our goal is usually to become root; as root we can do anything we like, so the system call I will add to the Linux kernel gives the caller real and effective user ids of zero.

There are relatively few tutorials out there on how to do this, unfortunately there a little differences between versions of Linux that can easily stump beginners, so this tutorial tries to give you an environment which you can easily replicate using a virtual machine and go through the tutorial.

Continue reading "Adding a malicious system call to the Linux kernel"