diff --git a/Gemfile.lock b/Gemfile.lock
index ccb35ef..9e19350 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -63,7 +63,8 @@ GEM
     rb-inotify (0.10.1)
       ffi (~> 1.0)
     regexp_parser (2.1.1)
-    rexml (3.2.5)
+    rexml (3.3.3)
+      strscan
     rouge (3.26.0)
     rubocop (1.15.0)
       parallel (~> 1.10)
@@ -89,6 +90,7 @@ GEM
       simplecov_json_formatter (~> 0.1)
     simplecov-html (0.12.3)
     simplecov_json_formatter (0.1.3)
+    strscan (3.1.0)
     unicode-display_width (2.0.0)
 
 PLATFORMS