diff --git a/frontend/Dockerfile b/frontend/Dockerfile
index e04e3b9..b55e33d 100644
--- a/frontend/Dockerfile
+++ b/frontend/Dockerfile
@@ -10,7 +10,7 @@
 
 RUN ./node_modules/webpack-cli/bin/cli.js --mode production
 
-FROM nginx:1.21-alpine
+FROM nginx:1.21-alpine@sha256:a74534e76ee1121d418fa7394ca930eb67440deda413848bc67c68138535b989
 LABEL maintainer "me@avm99963.com"
 
 COPY --from=build-stage /app/dist /usr/share/nginx/html