diff --git a/Gemfile b/Gemfile
index ad3c114..206aaf1 100644
--- a/Gemfile
+++ b/Gemfile
@@ -13,7 +13,7 @@ group :assets do
   gem 'sass-rails',   '3.2.5'
   gem 'coffee-rails', '3.2.2'
 
-  gem 'uglifier', '1.2.3'
+  gem 'uglifier', '2.7.2'
 end
 
 gem 'jquery-rails', '2.0.2'
diff --git a/Gemfile.lock b/Gemfile.lock
index 0a5433b..ceda814 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -39,7 +39,7 @@ GEM
     coffee-script-source (1.12.2)
     concurrent-ruby (1.1.8)
     erubis (2.7.0)
-    execjs (2.7.0)
+    execjs (2.8.1)
     hike (1.2.3)
     i18n (0.9.5)
       concurrent-ruby (~> 1.0)
@@ -97,9 +97,9 @@ GEM
       polyglot
       polyglot (>= 0.3.1)
     tzinfo (0.3.60)
-    uglifier (1.2.3)
+    uglifier (2.7.2)
       execjs (>= 0.3.0)
-      multi_json (>= 1.0.2)
+      json (>= 1.8.0)
 
 PLATFORMS
   ruby
@@ -111,7 +111,7 @@ DEPENDENCIES
   rails (= 3.2.17)
   sass-rails (= 3.2.5)
   sqlite3 (= 1.3.13)
-  uglifier (= 1.2.3)
+  uglifier (= 2.7.2)
 
 RUBY VERSION
    ruby 2.4.10p364