diff --git a/images/ranger/Dockerfile b/images/ranger/Dockerfile
index 43600583..d89d3eb6 100644
--- a/images/ranger/Dockerfile
+++ b/images/ranger/Dockerfile
@@ -1,4 +1,4 @@
-ARG BASE_IMAGE=ubuntu:18.04
+ARG BASE_IMAGE
 FROM ${BASE_IMAGE}
 
 ENV DEBIAN_FRONTEND noninteractive
diff --git a/images/rangercli/Dockerfile b/images/rangercli/Dockerfile
index fc0cefa4..5553995a 100644
--- a/images/rangercli/Dockerfile
+++ b/images/rangercli/Dockerfile
@@ -1,4 +1,4 @@
-ARG BASE_IMAGE=ubuntu:18.04
+ARG BASE_IMAGE
 FROM ${BASE_IMAGE}
 
 #ubuntu environment variables