rkhunter ... doesn't support redhat ES 4 (nahant update 3)?
actually, it does. but version 1.28 (the latest version as of this writing) doesn't recognize it.
if you're running rkhunter and get the following message:
Determining OS... Unknown
Warning: This operating system is not fully supported!
Warning: Cannot find md5_not_known
All MD5 checks will be skipped!
you can get rkhunter to acknowledge your OS by doing the following:
# cd usr/local/rkhunter/lib/rkhunter/db
# pico os.dat
(i'm still a fan of vi, but i'm trying to be tolerant) :)
in this file, look for like 189. add this line immediately below as such:
190:Red Hat Enterprise Linux ES release 4 (Nahant Update 3):/usr/bin/md5sum:/bin
save the file and then run rkhunter -c once again.