diff --git a/package.json b/package.json
index beeb5744..11e38202 100644
--- a/package.json
+++ b/package.json
@@ -48,12 +48,12 @@
     "google-closure-compiler": "^20161201.0.0",
     "grunt": "^1.0.1",
     "grunt-contrib-clean": "^1.0.0",
-    "grunt-contrib-compress": "^1.3.0",
+    "grunt-contrib-compress": "^2.0.0",
     "grunt-contrib-copy": "^1.0.0",
-    "grunt-contrib-cssmin": "^1.0.2",
-    "grunt-contrib-uglify": "^2.0.0",
+    "grunt-contrib-cssmin": "^4.0.0",
+    "grunt-contrib-uglify": "^5.2.1",
     "grunt-preprocess": "^5.1.0",
-    "html-to-text": "^3.0.0",
+    "html-to-text": "^5.1.0",
     "zombie": "^5.0.5"
   }
 }