In files /etc/apache2/modules.d/00_mod_info.conf & /etc/apache2/modules.d/00_mod_status.conf line 'Require host 127.0.0.1' is wrong.
It should be 'Require ip 127.0.0.1' or 'Require local'
Second will match both localhost, 127.0.0.1 and ::1
I can confirm this bug, and add that /etc/apache2/modules.d/46_mod_ldap.conf also have this problem.
It would be great to fix this bug, as it took me like an hour to figure out why my server-status stopped working. The 'Require host 127.0.0.1' looks correct, but it actually acts like 'Require all denied'. As Nick suggested, 'Require local' would be best as it works with IPv6 localhost too.
Sorry Lars, I missed that bug when filling #509772 :/ It may be better to use this one to track the next gentoo-apache rollout
Fixed in =www-servers/apache-2.2.27-r3 and =www-servers/apache-2.4.9-r3.