diff --git a/Dockerfile b/Dockerfile
index b99723b..3e9d73e 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,4 +1,4 @@
-FROM openjdk:11.0.16
+FROM openjdk:11.0.16@sha256:99bac5bf83633e3c7399aed725c8415e7b569b54e03e4599e580fc9cdb7c21ab
 MAINTAINER Joakim Olsson <joakim@unbound.se>
 
 RUN apt-get update \