diff --git a/examples/cluster-haproxy/server/package.json b/examples/cluster-haproxy/server/package.json
index 0fe83ecd3e..255029fd54 100644
--- a/examples/cluster-haproxy/server/package.json
+++ b/examples/cluster-haproxy/server/package.json
@@ -7,7 +7,7 @@
   "private": true,
   "license": "BSD",
   "dependencies": {
-    "express": "4.13.4",
+    "express": "4.21.0",
     "socket.io": "^1.7.2",
     "socket.io-redis": "^3.0.0"
   },