SUID permissions means that, when a file is executed, that file runs with the permissions of the user or group that the file is owned by. For example, a file that is owned by root and has the suid bit set will execute as root, even when run by a user other then root. This can be useful at times, but usually it’s a bad idea. It’s good practice to crawl your filesystems periodically and look for files that have the suid bit set, it can sometimes be an indicator of foul play. You can do that using the find command like so
find / -perm -u+s -print
Have fun, be safe.
