diff --git a/Gemfile.lock b/Gemfile.lock
index e4fe4a7..fa4346c 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -22,7 +22,8 @@ GEM
     racc (1.7.1)
     rainbow (3.1.1)
     regexp_parser (2.8.1)
-    rexml (3.2.5)
+    rexml (3.3.3)
+      strscan
     rspec (3.12.0)
       rspec-core (~> 3.12.0)
       rspec-expectations (~> 3.12.0)
@@ -72,6 +73,7 @@ GEM
       terminal-table
     simplecov-html (0.12.3)
     simplecov_json_formatter (0.1.4)
+    strscan (3.1.0)
     terminal-table (3.0.2)
       unicode-display_width (>= 1.1.1, < 3)
     unicode-display_width (2.4.2)