diff --git a/Gemfile b/Gemfile
index d3faaaf05..85d62654c 100644
--- a/Gemfile
+++ b/Gemfile
@@ -25,7 +25,7 @@ gem 'validates_email_format_of', '1.6.3' # validates email against RFC 2822 and
 
 # 0.7.3 is the latest for Rails 4.2, however, it is absent on Rubygems server
 # https://github.com/huacnlee/rails-settings-cached/issues/165
-gem 'nokogiri', '~> 1.10.0'
+gem 'nokogiri', '~> 1.11.0'
 
 # style
 gem 'bootstrap-sass', '~> 3.4'
diff --git a/Gemfile.lock b/Gemfile.lock
index 3e411fa8c..dd41719ad 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -290,7 +290,7 @@ GEM
       nokogiri (~> 1)
       rake
     mini_mime (1.1.0)
-    mini_portile2 (2.4.0)
+    mini_portile2 (2.5.1)
     minitest (5.14.4)
     monetize (1.9.4)
       money (~> 6.12)
@@ -307,8 +307,11 @@ GEM
       ruby2_keywords (~> 0.0.1)
     netrc (0.11.0)
     nio4r (2.5.7)
-    nokogiri (1.10.10)
-      mini_portile2 (~> 2.4.0)
+    nokogiri (1.11.0)
+      mini_portile2 (~> 2.5.0)
+      racc (~> 1.4)
+    nokogiri (1.11.0-x86_64-linux)
+      racc (~> 1.4)
     nori (2.6.0)
     omniauth (1.9.1)
       hashie (>= 3.4.6)
@@ -343,6 +346,7 @@ GEM
       erubis
       que (~> 0.8)
       sinatra
+    racc (1.5.2)
     rack (2.2.3)
     rack-oauth2 (1.16.0)
       activesupport
@@ -543,7 +547,7 @@ DEPENDENCIES
   mimemagic (= 0.3.10)
   minitest (~> 5.14)
   money-rails
-  nokogiri (~> 1.10.0)
+  nokogiri (~> 1.11.0)
   omniauth
   omniauth-rails_csrf_protection
   omniauth-tara!