diff --git a/Gemfile.lock b/Gemfile.lock
index abb7b16..adc0063 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -1,7 +1,7 @@
 GEM
   remote: https://rubygems.org/
   specs:
-    asciidoctor (2.0.17)
+    asciidoctor (2.0.20)
 
 PLATFORMS
   ruby