diff --git a/image/Dockerfile b/image/Dockerfile
index ed32651..637f4a3 100644
--- a/image/Dockerfile
+++ b/image/Dockerfile
@@ -1,5 +1,5 @@
 FROM docker.io/alpine:3.21
-RUN apk add openjdk17-jre
+RUN apk add openjdk21-jre
 RUN adduser -u 1000 -h /var/server -D execute
 RUN mkdir -p /var/exec