Linux Hint published a tutorial about installing Chkrootkit on Debian based Linux distributions.

How to Install Chkrootkit

This tutorial focuses on rootkits and how to detect them using chkrootkit. Rootkits are tools designed to grant access or privileges while hiding their own presence, or the presence of an additional software granting the access, the “rootkit” term focuses on hiding aspect. Since rootkits have a variety of ways to achieve its goals hiding malicious software, Chkrootkit offers a variety of tools to afford these ways. How to install chkrootkit on Linux is shown in this tutorial.

How to Install Chkrootkit