diff --git a/misc/s3-sync/Dockerfile b/misc/s3-sync/Dockerfile
index cec5831..84936ae 100644
--- a/misc/s3-sync/Dockerfile
+++ b/misc/s3-sync/Dockerfile
@@ -1,6 +1,6 @@
 # syntax=docker/dockerfile:1
 
-ARG ALPINE_VERSION=3.20.5
+ARG ALPINE_VERSION=3.21.2
 
 FROM alpine:${ALPINE_VERSION} AS base
 
diff --git a/php/Dockerfile b/php/Dockerfile
index 282e82c..eb326f6 100644
--- a/php/Dockerfile
+++ b/php/Dockerfile
@@ -6,7 +6,7 @@ ARG PHP_SHORT_VERSION=82
 #
 # libiconv
 #
-FROM alpine:3.13 AS libiconv
+FROM alpine:3.21 AS libiconv
 
 RUN apk --no-cache add gnu-libiconv && test -f /usr/lib/preloadable_libiconv.so