diff --git a/src/build/less-js/package.json b/src/build/less-js/package.json
index 07a339cf9..177216a67 100644
--- a/src/build/less-js/package.json
+++ b/src/build/less-js/package.json
@@ -47,7 +47,7 @@
     "source-map": "0.1.x"
   },
   "devDependencies": {
-    "diff": "~1.0",
+    "diff": "~4.0",
     "grunt": "~0.4.1",
     "grunt-contrib-clean": "~0.5.0",
     "grunt-contrib-concat": "~0.3.0",