diff --git a/Dockerfile b/Dockerfile
index 0a07bd8..c334bff 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,4 +1,4 @@
-FROM alpine:3.5
+FROM alpine:3.8
 
 RUN apk add -U ca-certificates tzdata && rm -Rf /var/cache/apk/*
 COPY cm /