I am running 12.04 (LTS), which has version 1.3.8-10 of the package rkhunter. The rkhunter web site flashes at you the message:
Rootkit Hunter release 1.4.0 obsoletes all previous releases. Please upgrade real soon now.
The problem of what to do is more general than just rkhunter, but it makes a good example of a general problem.
Q1: Should I do this by using a package from a later version of Ubuntu? (Eg, 13-04 has version 1.4.0-2 of rkhunter.) How is that done, and what are the risks?
Q2. Or should I download rkhunter-1.4.0.tar.gz from sourceforge, unzip it, and try to work out which files go where. Are there risks with that?
Q3. And how do you recommend that I try to avoid overwriting changes I have made to config files, cron jobs etc.
Q4: Anyway, you would think this is a security update. So why is it not included in 12.04?