diff --git a/web/Dockerfile b/web/Dockerfile
index 4d3d66f..e420162 100644
--- a/web/Dockerfile
+++ b/web/Dockerfile
@@ -1,5 +1,5 @@
 # syntax = docker/dockerfile:1.3
-FROM alpine:3.20.3
+FROM alpine:3.21.0
 
 # Add requirements file.
 COPY requirements.txt /tmp/
diff --git a/web/Dockerfile.dev b/web/Dockerfile.dev
index bb7f15d..f5b5b69 100644
--- a/web/Dockerfile.dev
+++ b/web/Dockerfile.dev
@@ -1,5 +1,5 @@
 # syntax = docker/dockerfile:1.3
-FROM alpine:3.20.3
+FROM alpine:3.21.0
 
 ARG POSTORIUS_REF
 ARG HYPERKITTY_REF