DISCUSSION: Finding Rootkits, Infections, and Files

This thread is to discuss the article titled: Finding Rootkits, Infections, and Files

The offer for discussion seams interesting to me, as I support few servers in my town - all of them using debian.

One of those machines is set up with knoppix 3.2 from which I removed a lot of stuff that was not needed, so afterwards few months later I ran chkrootkit on it and it says there is probably LKM attack as 4 Processes are hidden from the ps command.

And really when I ps -A I don't see process numbers
1 ? 00:00:10 init
2 ? 00:00:00 keventd
0 ? 00:00:00 ksoftirqd_CPU0
0 ? 00:00:00 kswapd
0 ? 00:00:00 bdflush
0 ? 00:00:01 kupdated

I read about this, that it should be a problem with multithereading on debian in some cases, but honestly I haven't had this problem on other debian system.

I suppose it has to do something with knoppix but I don't have a machine like this.

After I spent hours of checking logs and so, I concluded that there isn't anything wrong

What is your oppinion?

Are you aware of security issues with knoppix

Thanks

from http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=222179

That's a bug in chkrootkit. With the latest glibc and 2.6 kernel, the threading model has changed. Threads no longer show up as individual processes. Chkrootkit should be updated to work with the latest glibc and 2.6 kernel (i.e. it should check /proc/<pid>/task too)

I don't see a fix posted there though. What version of chkrootkit are you running?

--jeremy

thanks jeremy
I see, but I am using the 2.4.22-xfs kernel on this machine that comes with knoppix

Even tho I think this is somewhat OT, 0.44-beta is just around the corner.
If all is well it will feature an improved threading aware chkproc.