This has been fixed in the 7.3 branch. https://bugzilla.redhat.com/show_bug.cgi?id=1286756

Need to confirm that the fix has been ported to 8

This is also done upstream, so it should make OSP 8: https://review.openstack.org/#/c/259578/

Verifed on 
instack-undercloud-2.2.2-1.el7ost.noarch

root@instack:~ $ iptables-save | egrep '13000|13774|13696|13385|13292|13696|13004|13080|13385'
-A INPUT -p tcp -m multiport --dports 8000,8003,8004,13800,13003,13004 -j ACCEPT
-A INPUT -p tcp -m multiport --dports 6385,13385 -j ACCEPT
-A INPUT -p tcp -m multiport --dports 9292,13292 -j ACCEPT
-A INPUT -p tcp -m multiport --dports 6080,13080 -j ACCEPT
-A INPUT -p tcp -m multiport --dports 9696,13696 -j ACCEPT
-A INPUT -p tcp -m multiport --dports 5000,35357,13000,13357 -j ACCEPT
-A INPUT -p tcp -m multiport --dports 8773,8774,8775,13773,13774,13775 -j ACCEPT

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://rhn.redhat.com/errata/RHEA-2016-0604.html