Sometimes it’s necessary to run a process as non priviledged user on a port lower than 1024.

Assuming there is a non priviledged user called “usernonpriv”

On Solaris 10 and 11 you can run

usermod -K defaultpriv=basic,net_privaddr usernonpriv

This will allow that user “usernonpriv” can start a process listeing on port 80 or 443

It adds a line to /etc/user_attr

usernonpriv::::defaultpriv=basic,net_privaddr