diff --git a/Dockerfile b/Dockerfile
index b1e958b7..63953434 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,5 +1,5 @@
 # Main stage
-FROM alpine:3.20.3@sha256:1e42bbe2508154c9126d48c2b8a75420c3544343bf86fd041fb7527e017a4b4a
+FROM alpine:3.21.0@sha256:21dc6063fd678b478f57c0e13f47560d0ea4eeba26dfc947b2a4f81f686b9f45
 
 # Copy necessary files
 COPY scripts /scripts
diff --git a/Dockerfile-fat b/Dockerfile-fat
index 92a3837d..2d9cc944 100644
--- a/Dockerfile-fat
+++ b/Dockerfile-fat
@@ -12,7 +12,7 @@ RUN DOCKER_ENABLE_SECURITY=true \
 ./gradlew clean build
 
 # Main stage
-FROM alpine:3.20.3
+FROM alpine:3.21.0@sha256:21dc6063fd678b478f57c0e13f47560d0ea4eeba26dfc947b2a4f81f686b9f45
 
 # Copy necessary files
 COPY scripts /scripts
diff --git a/Dockerfile-ultra-lite b/Dockerfile-ultra-lite
index 1aac6002..1d87253d 100644
--- a/Dockerfile-ultra-lite
+++ b/Dockerfile-ultra-lite
@@ -1,5 +1,5 @@
 # use alpine
-FROM alpine:3.21.0
+FROM alpine:3.21.0@sha256:21dc6063fd678b478f57c0e13f47560d0ea4eeba26dfc947b2a4f81f686b9f45
 
 ARG VERSION_TAG