diff --git a/Dockerfile b/Dockerfile
index fc7ed5f..48968cb 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -32,7 +32,7 @@ RUN rm /app/build/distributions/mahjong-points.js.map
 #**************************************
 
 # local build only
-FROM alpine:3.18.2 AS local-postinstall
+FROM alpine:3.18.3 AS local-postinstall
 WORKDIR /app
 RUN apk update \
  && apk add lighttpd \
@@ -40,7 +40,7 @@ RUN apk update \
 COPY --from=TEMP_BUILD_IMAGE /app/build/distributions /var/www/localhost/htdocs
 
 # github action only
-FROM alpine:3.18.2 AS github-postinstall
+FROM alpine:3.18.3 AS github-postinstall
 WORKDIR /app
 RUN apk update \
  && apk add lighttpd \