diff --git a/CHANGELOG b/CHANGELOG
index 499febdfd08aae83bc9adcccfa0a78e266be2b50..3785506b1f5a25d62d5bd5fd273d3c336c8fceb7 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -39,6 +39,7 @@ v 8.8.0 (unreleased)
   - Expire repository exists? and has_visible_content? caches after a push if necessary
   - Fix unintentional filtering bug in issues sorted by milestone due (Takuya Noguchi)
   - Fix adding a todo for private group members (Ahmad Sherif)
+  - Bump ace-rails-ap gem version from 2.0.1 to 4.0.2 which upgrades Ace Editor from 1.1.2 to 1.2.3
 
 v 8.7.4
   - Fix always showing build notification message when switching between merge requests
diff --git a/Gemfile b/Gemfile
index 3e5c604ae06ed0a0da0381753dfb8ab69fe008cb..77d351419f0c1e50e85a2015cd90f249685885f7 100644
--- a/Gemfile
+++ b/Gemfile
@@ -197,7 +197,7 @@ gem 'licensee', '~> 8.0.0'
 gem "rack-attack", '~> 4.3.1'
 
 # Ace editor
-gem 'ace-rails-ap', '~> 2.0.1'
+gem 'ace-rails-ap', '~> 4.0.2'
 
 # Keyboard shortcuts
 gem 'mousetrap-rails', '~> 1.4.6'
diff --git a/Gemfile.lock b/Gemfile.lock
index 86b9142ef27deea1f12867a965620a953cdf22bb..c02698bcca749791c75fd45d5c492e4055c586fb 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -3,7 +3,7 @@ GEM
   specs:
     CFPropertyList (2.3.2)
     RedCloth (4.2.9)
-    ace-rails-ap (2.0.1)
+    ace-rails-ap (4.0.2)
     actionmailer (4.2.6)
       actionpack (= 4.2.6)
       actionview (= 4.2.6)
@@ -882,7 +882,7 @@ PLATFORMS
 
 DEPENDENCIES
   RedCloth (~> 4.2.9)
-  ace-rails-ap (~> 2.0.1)
+  ace-rails-ap (~> 4.0.2)
   activerecord-deprecated_finders (~> 1.0.3)
   activerecord-session_store (~> 0.1.0)
   acts-as-taggable-on (~> 3.4)