diff --git a/ipv6/mx.cidr b/ipv6/mx.cidr
index b6da78342..98e6ec02e 100644
--- a/ipv6/mx.cidr
+++ b/ipv6/mx.cidr
@@ -173,5 +173,5 @@
 2806:42c::/31
 2806:42e::/32
 2806:430::/30
-2806:434::/32
+2806:434::/31
 2806:1000::/24