diff --git a/Gemfile.lock b/Gemfile.lock
index c5518ae..382e3f3 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -204,7 +204,9 @@ GEM
     mime-types (3.2.2)
       mime-types-data (~> 3.2015)
     mime-types-data (3.2018.0812)
-    mimemagic (0.3.2)
+    mimemagic (0.4.3)
+      nokogiri (~> 1)
+      rake
     mini_magick (4.6.1)
     mini_mime (1.0.1)
     mini_portile2 (2.3.0)
@@ -224,7 +226,7 @@ GEM
     os (0.9.6)
     public_suffix (2.0.5)
     puma (3.6.2)
-    rack (1.6.10)
+    rack (1.6.13)
     rack-test (0.6.3)
       rack (>= 1.0)
     rails (4.2.10)