diff --git a/package-lock.json b/package-lock.json
index 73ad6d032..a08f6f429 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -7891,9 +7891,9 @@
       "dev": true
     },
     "uglify-js": {
-      "version": "3.5.8",
-      "resolved": "https://registry.npmjs.org/uglify-js/-/uglify-js-3.5.8.tgz",
-      "integrity": "sha512-GFSjB1nZIzoIq70qvDRtWRORHX3vFkAnyK/rDExc0BN7r9+/S+Voz3t/fwJuVfjppAMz+ceR2poE7tkhvnVwQQ==",
+      "version": "3.5.9",
+      "resolved": "https://registry.npmjs.org/uglify-js/-/uglify-js-3.5.9.tgz",
+      "integrity": "sha512-WpT0RqsDtAWPNJK955DEnb6xjymR8Fn0OlK4TT4pS0ASYsVPqr5ELhgwOwLCP5J5vHeJ4xmMmz3DEgdqC10JeQ==",
       "dev": true,
       "requires": {
         "commander": "~2.20.0",
diff --git a/package.json b/package.json
index 8551cc69e..bd070daff 100644
--- a/package.json
+++ b/package.json
@@ -71,7 +71,7 @@
     "rollup-plugin-buble": "^0.19.6",
     "rollup-plugin-node-resolve": "4.2.3",
     "rollup-plugin-sizes": "^0.5.1",
-    "uglify-js": "3.5.8"
+    "uglify-js": "3.5.9"
   },
   "scripts": {
     "start": "ws",