diff --git a/Gemfile b/Gemfile
index 17ba11a..222c3c5 100644
--- a/Gemfile
+++ b/Gemfile
@@ -14,7 +14,7 @@ gem 'redcarpet', '~> 3.6'
 gem 'pygments.rb', '~> 2.4'
 
 # 1.14.0 is Ruby 2.7 only
-gem 'nokogiri', '~> 1.16.7'
+gem 'nokogiri', '~> 1.18.1'
 
 # 1.17.0 does not seem to work on Ruby 2.6:
 # https://github.com/perlun/perlun.eu.org/actions/runs/9685245708/job/26724904172?pr=50.
diff --git a/Gemfile.lock b/Gemfile.lock
index 8a8043d..cbb9603 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -66,18 +66,18 @@ GEM
       rb-fsevent (~> 0.10, >= 0.10.3)
       rb-inotify (~> 0.9, >= 0.9.10)
     mercenary (0.3.6)
-    mini_portile2 (2.8.7)
+    mini_portile2 (2.8.8)
     minitest (5.23.1)
-    nokogiri (1.16.7)
+    nokogiri (1.18.1)
       mini_portile2 (~> 2.8.2)
       racc (~> 1.4)
-    nokogiri (1.16.7-x86_64-linux)
+    nokogiri (1.18.1-x86_64-linux-gnu)
       racc (~> 1.4)
     pathutil (0.16.2)
       forwardable-extended (~> 2.6)
     public_suffix (5.1.1)
     pygments.rb (2.4.1)
-    racc (1.8.0)
+    racc (1.8.1)
     rb-fsevent (0.11.2)
     rb-inotify (0.11.1)
       ffi (~> 1.0)
@@ -107,7 +107,7 @@ DEPENDENCIES
   jekyll-multiple-languages-plugin!
   jekyll-paginate (~> 1.1)
   jemoji (~> 0.13)
-  nokogiri (~> 1.16.7)
+  nokogiri (~> 1.18.1)
   pygments.rb (~> 2.4)
   redcarpet (~> 3.6)