diff --git a/docs/examples/session-affinity/Dockerfile b/docs/examples/session-affinity/Dockerfile
index 89f6bb1fd5a..5a2700c0677 100644
--- a/docs/examples/session-affinity/Dockerfile
+++ b/docs/examples/session-affinity/Dockerfile
@@ -1,4 +1,4 @@
-FROM alpine:3.15.6
+FROM alpine:3.21.3
 
 RUN apk upgrade --update-cache \
     && apk add ca-certificates \