Package: chkrootkit

"chkrootkit" package binaries on CentOS:

/usr/bin/chkrootkit /usr/bin/chkrootkitX /usr/sbin/chkrootkit

You may install this package on CentOS with yum install chkrootkit

"chkrootkit" package binaries on Debian:

/usr/sbin/chklastlog /usr/sbin/chkrootkit /usr/sbin/chkwtmp

You may install this package on Debian with apt-get install chkrootkit