diff --git a/Gemfile.lock b/Gemfile.lock
index 45ffc14..5b44fcb 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -25,7 +25,8 @@ GEM
     rainbow (3.1.1)
     rake (13.0.6)
     regexp_parser (2.8.1)
-    rexml (3.2.6)
+    rexml (3.2.8)
+      strscan (>= 3.0.9)
     rspec (3.12.0)
       rspec-core (~> 3.12.0)
       rspec-expectations (~> 3.12.0)
@@ -68,6 +69,7 @@ GEM
       simplecov_json_formatter (~> 0.1)
     simplecov-html (0.12.3)
     simplecov_json_formatter (0.1.4)
+    strscan (3.1.0)
     unicode-display_width (2.4.2)
     yard (0.9.34)