After a recent break in on a machine running Linux, I found an executable file in the home folder of a user with a weak password. I have cleaned up what appears to be all the damage, but am preparing a full wipe to be sure.
What can malware run by a NON-sudo or unprivileged user do? Is it just looking for files marked with world writable permission to infect? What threatening things can a non-admin user do on most Linux systems? Can you provide some examples of real world problems this kind of security breach can cause?