diff --git a/Dockerfile b/Dockerfile
index 4db086b..8333e18 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,4 +1,4 @@
-FROM ruby:2.4.0-onbuild
+FROM ruby:2.4.4-onbuild
 LABEL maintainer "Gebhard Woestemeyer <g@ctr.lc>"
 ENV LANG=C.UTF-8
 WORKDIR /app