If your system has been compromised, or if you think it might have been compromised,
you should immediately check for files that may have been modified by the intruder.
The intruder may have changed files in an extremely subtle way to install a backdoor so they can break into the system again.
For example, the intruder might alter a standard script so that a particular parameter opens a backdoor,
or he or she may simply make a vulnerable script sticky, or executable only by the script's owner, so they can use it to break root
.
The find
command is an extremely useful utility for finding such changes.
For more information, consult the man pages using the command man find.
The next lesson describes the
cron
facility.
Potentially Cracked Abused Files
Click on the link to learn about Potentially Cracked Abused Files.