rapid7/metasploit-framework — pull request #3478 by dmaloney-r7 (2014-06-25 19:14:16+00:00)
Title: Fix portspec allowing port 0

A change was made to allow portspec to include 0. This was intentionally not allowed before. the RFC does not allow the use of port 0. We have code that depends on portspec not allowing it. Additionally no socket implementation allows you to bind to port 0. If you try to bind to port 0 it binds to a random available port, not port 0.