Using 'netstat -tulp' on my server box running under CentOS I have discovered strange listening ports 33363 (TCP) and 35661 (UDP). The thing is that 'PID/Program name' field for these ports contains nothing (dash actually). 'fuser -n tcp 33363' shows nothing. I have checked my box with chkrootkit and rkhunter utilities and it seems everything is O.K. Does anybody know what these sockets can be used for?