diff --git a/Gemfile b/Gemfile
index 371f6b3..ac60d84 100644
--- a/Gemfile
+++ b/Gemfile
@@ -1,6 +1,6 @@
 source 'https://rubygems.org'
 
-gem 'nokogiri', '~> 1.11.0'
+gem 'nokogiri', '~> 1.13.9'
 gem 'premailer', '~> 1.11', '>= 1.11.1'
 
 group :test do
diff --git a/Gemfile.lock b/Gemfile.lock
index 9e82e34..2d7ac86 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -6,17 +6,17 @@ GEM
     css_parser (1.7.1)
       addressable
     htmlentities (4.3.4)
-    mini_portile2 (2.5.0)
+    mini_portile2 (2.8.0)
     minitest (5.14.0)
-    nokogiri (1.11.0)
-      mini_portile2 (~> 2.5.0)
+    nokogiri (1.13.9)
+      mini_portile2 (~> 2.8.0)
       racc (~> 1.4)
     premailer (1.11.1)
       addressable
       css_parser (>= 1.6.0)
       htmlentities (>= 4.0.0)
     public_suffix (4.0.3)
-    racc (1.5.2)
+    racc (1.6.0)
     rake (13.0.1)
 
 PLATFORMS
@@ -24,7 +24,7 @@ PLATFORMS
 
 DEPENDENCIES
   minitest (~> 5.14.0)
-  nokogiri (~> 1.11.0)
+  nokogiri (~> 1.13.9)
   premailer (~> 1.11, >= 1.11.1)
   rake (~> 13.0.1)