diff --git a/Gemfile.lock b/Gemfile.lock
index eff3776..9383eba 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -84,7 +84,8 @@ GEM
     regexp_parser (2.9.0)
     reverse_markdown (2.1.1)
       nokogiri
-    rexml (3.2.6)
+    rexml (3.3.3)
+      strscan
     rspec (3.13.0)
       rspec-core (~> 3.13.0)
       rspec-expectations (~> 3.13.0)
@@ -135,6 +136,7 @@ GEM
       thor (~> 1.0)
       tilt (~> 2.0)
       yard (~> 0.9, >= 0.9.24)
+    strscan (3.1.0)
     thor (1.0.1)
     thread_safe (0.3.6)
     tilt (2.3.0)