diff --git a/Gemfile.lock b/Gemfile.lock
index 8b10efde440..8276b976652 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -235,7 +235,7 @@ GEM
     mini_suffix (0.3.3)
       ffi (~> 1.9)
     minio_runner (0.1.2)
-    minitest (5.20.0)
+    minitest (5.21.1)
     mocha (2.1.0)
       ruby2_keywords (>= 0.0.5)
     msgpack (1.7.2)