diff --git a/Gemfile.lock b/Gemfile.lock
index e79224bbf..6cb4f9c16 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -487,7 +487,7 @@ GEM
       activesupport
     rack-mobile-detect (0.4.0)
       rack
-    rack-oauth2 (1.4.0)
+    rack-oauth2 (1.5.1)
       activesupport (>= 2.3)
       attr_required (>= 0.0.5)
       httpclient (>= 2.4)