What's netbiosd? I must block netbiosd?
From Apple's netbiosd man page:


  netbiosd is responsible for interacting with NetBIOS networks.  netbiosd registers and defends one or more NetBIOS name, depending on the set of configured services. It also browses and scavenges names from the NetBIOS network, making them available to the system through mDNSResponder.


Simply put, no, netbiosd is a perfectly safe daemon included in OS X by Apple.