diff --git a/data/powerdns/files/bind-zones/kunbox.net b/data/powerdns/files/bind-zones/kunbox.net
index 7c75676..4ff5d3c 100644
--- a/data/powerdns/files/bind-zones/kunbox.net
+++ b/data/powerdns/files/bind-zones/kunbox.net
@@ -13,6 +13,8 @@ $ORIGIN kunbox.net.
 mx0                 IN  A       94.130.52.224
                     IN  AAAA    2a01:4f8:10b:2a5f::2
                     IN  AAAA    2a01:4f8:10b:2a5f::1337
+mta-sts             IN  CNAME   mx0
+mta-sts             IN  CNAME   mx0
 mta-sts.mx0         IN  CNAME   mx0
 mta-sts.mx0         IN  CNAME   mx0
 postfixadmin.mx0    IN  CNAME   mx0