Scan applications without default port

It could be possible that this here doesn’t work against newer PostgreSQL versions anymore:

You could try to modify postgresql_detect.nasl to replace:

  script_require_ports("Services/postgresql", 5432);

by:

  script_require_ports("Services/postgresql", "Services/unknown", 5432);

and:

port = unknownservice_get_port(default:5432);

with the following below as a follow-up to see if this is working out for your case.