diff --git a/Gemfile b/Gemfile
index f8904b26d..c842ac8ed 100644
--- a/Gemfile
+++ b/Gemfile
@@ -3,7 +3,7 @@ source 'https://rubygems.org'
 gem 'rake', '13.2.1'
 gem 'asciidoctor', '2.0.22'
 
-gem 'json', '2.7.6'
+gem 'json', '2.8.1'
 gem 'awesome_print', '1.9.2'
 
 gem 'asciidoctor-fb2', '0.7.0'