diff --git a/Gemfile.lock b/Gemfile.lock
index 3e0d64527..aee492b38 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -112,7 +112,7 @@ GEM
       launchy (~> 2.1)
       mail (~> 2.2)
     erubis (2.7.0)
-    execjs (2.5.0)
+    execjs (2.7.0)
     factory_girl (4.5.0)
       activesupport (>= 3.0.0)
     faraday (0.9.1)
@@ -138,7 +138,6 @@ GEM
       jquery-rails
       jquery-ui-rails (= 4.0.3)
       railties (>= 3.1.0)
-    json (1.8.2)
     jwt (1.4.1)
     kaminari (0.16.3)
       actionpack (>= 3.0.0)
@@ -291,9 +290,8 @@ GEM
     turbolinks (2.5.3)
       coffee-rails
     tzinfo (0.3.55)
-    uglifier (2.7.1)
-      execjs (>= 0.3.0)
-      json (>= 1.8.0)
+    uglifier (4.1.20)
+      execjs (>= 0.3.0, < 3)
     warden (1.2.7)
       rack (>= 1.0)
     xpath (2.0.0)