diff --git a/Gemfile.lock b/Gemfile.lock
index 5610a3c..5544643 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -21,9 +21,11 @@ GEM
     power_assert (1.1.4)
     public_suffix (4.0.6)
     rake (13.0.3)
-    rexml (3.2.5)
+    rexml (3.3.2)
+      strscan
     rr (1.2.1)
     safe_yaml (1.0.5)
+    strscan (3.1.0)
     test-unit (3.3.3)
       power_assert
     test-unit-context (0.5.1)