diff --git a/Gemfile.lock b/Gemfile.lock
index 1c9ac48..23a68f5 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -320,7 +320,9 @@ GEM
     mime-types (3.1)
       mime-types-data (~> 3.2015)
     mime-types-data (3.2016.0521)
-    mimemagic (0.3.2)
+    mimemagic (0.4.3)
+      nokogiri (~> 1)
+      rake
     mini_magick (4.5.1)
     mini_portile2 (2.1.0)
     minitest (5.9.0)
@@ -524,12 +526,12 @@ GEM
       eventmachine (~> 1.0, >= 1.0.4)
       rack (>= 1, < 3)
     thor (0.19.1)
-    thread_safe (0.3.5)
+    thread_safe (0.3.6)
     tilt (2.0.5)
     time_difference (0.4.2)
       activesupport
     trollop (2.1.2)
-    tzinfo (1.2.2)
+    tzinfo (1.2.10)
       thread_safe (~> 0.1)
     uglifier (3.0.1)
       execjs (>= 0.3.0, < 3)