diff --git a/Gemfile.lock b/Gemfile.lock
index c03650ce..5d1ef58d 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -92,6 +92,7 @@ GEM
       rack-test (>= 0.5.4)
       xpath (~> 2.0)
     coderay (1.1.0)
+    concurrent-ruby (1.1.5)
     cucumber (1.3.20)
       builder (>= 2.1.2)
       diff-lcs (>= 1.1.3)
@@ -186,7 +187,7 @@ GEM
       omniauth (~> 1.2.0)
     pg (0.18.4)
     pothoven-attachment_fu (3.2.16)
-    rack (1.6.4)
+    rack (1.6.11)
     rack-test (0.6.3)
       rack (>= 1.0)
     rails (4.2.5)
@@ -265,7 +266,8 @@ GEM
       json (~> 1.8)
       simplecov-html (~> 0.10.0)
     simplecov-html (0.10.0)
-    sprockets (3.4.1)
+    sprockets (3.7.2)
+      concurrent-ruby (~> 1.0)
       rack (> 1, < 3)
     sprockets-rails (2.3.3)
       actionpack (>= 3.0)