Re: chkrootkit and LKM?

[Guille -bisho- <bisho () onirica com>]

> I using a RHL9 as my workstation. A few days ago I downloaded chkrootkit
> and it consistently gives the same output (>20 hidden processes) when
> checking for LKM rootkit:
>
> Checking `lkm'... You have    38 process hidden for readdir command
> Warning: Possible LKM Trojan installed
>
> This is even after reboots. How can I check if this is actually the work
> of the LKM? Or any other rootkit for that matter?

You should reinstall. init is usually reemplaced with a infected one
that inserts the rootkit module in the kernel, and the same with many
other programs.

If you have the same OS version in another machine you could check the
md5sum of all the binaries, and reemplace them from the clean machine,
booting from an uninfected source like a CD or in another machine
installing without booting from it the infected hard disc.

Anyway, I would never trust that machine anymore. I recomend to backup
only the data and reinstall the OS.

-- 
bisho!  _        -=] 17/06/2003 [=-
    _ ^(   )       _
   (  (   )  )     \ \___,,,
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  '. |::| ,  >==-
    \\:://  [ PAZ SI, GUERRA NO ]



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