Linux – The PID and name of the program to which socket belongs

You'd rather use pfiles which is part of Solaris and supported by Sun, unlike lsof.

Its usage is slightly different as it expects a pid as argument but you can achieve what you want with something like:

pfiles $(pgrep libhttpd)

or even, if you don't know the process name:

pfiles /proc/*  

From data you provided I'd say it's related to some NFS mounts or something using RPC.

you can check with rpcinfo -p for ports that might be used by some of RPC related services.

Here is how it looks on my system

# netstat -nlp | awk '{if ($NF == "-")print $0}'
tcp        0      0 0.0.0.0:55349           0.0.0.0:*               LISTEN      -               
udp        0      0 0.0.0.0:18049           0.0.0.0:*                           - 

# rpcinfo -p
   program vers proto   port
    100000    2   tcp    111  portmapper
    100000    2   udp    111  portmapper
    100024    1   udp  10249  status
    100024    1   tcp  10249  status
    100021    1   udp  18049  nlockmgr
    100021    3   udp  18049  nlockmgr
    100021    4   udp  18049  nlockmgr
    100021    1   tcp  55349  nlockmgr
    100021    3   tcp  55349  nlockmgr
    100021    4   tcp  55349  nlockmgr