diff --git a/scripts/installer/kexec/Dockerfile.dapper b/scripts/installer/kexec/Dockerfile.dapper
index 179ed7abc..50913a90c 100644
--- a/scripts/installer/kexec/Dockerfile.dapper
+++ b/scripts/installer/kexec/Dockerfile.dapper
@@ -1,4 +1,4 @@
-FROM ubuntu:16.04
+FROM ubuntu:xenial-20210416
 # FROM arm64=aarch64/ubuntu:16.04 arm=armhf/ubuntu:16.04
 
 # get the apt-cacher proxy set