diff --git a/Dockerfile b/Dockerfile
index 18b164f2..f466be99 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,4 +1,4 @@
-FROM alpine:3.8
+FROM alpine:3.15
 RUN apk add --no-cache ca-certificates
 
 ADD tile38-server /usr/local/bin