diff --git a/CHANGELOG b/CHANGELOG
index f8ae187348d..63077523aaa 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -35,6 +35,7 @@ v 8.8.0 (unreleased)
   - Fix Gravatar hint in user profile when Gravatar is disabled. !3988 (Artem Sidorenko)
   - 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)
 
 v 8.7.4
   - Fix always showing build notification message when switching between merge requests
diff --git a/app/models/concerns/mentionable.rb b/app/models/concerns/mentionable.rb
index 98f71ae8cb0..b381d225485 100644
--- a/app/models/concerns/mentionable.rb
+++ b/app/models/concerns/mentionable.rb
@@ -43,8 +43,8 @@ module Mentionable
     self
   end
 
-  def all_references(current_user = self.author, text = nil)
-    ext = Gitlab::ReferenceExtractor.new(self.project, current_user, self.author)
+  def all_references(current_user = nil, text = nil)
+    ext = Gitlab::ReferenceExtractor.new(self.project, current_user || self.author, self.author)
 
     if text
       ext.analyze(text)
diff --git a/spec/services/todo_service_spec.rb b/spec/services/todo_service_spec.rb
index 82b7fbfa816..a075496ee63 100644
--- a/spec/services/todo_service_spec.rb
+++ b/spec/services/todo_service_spec.rb
@@ -55,6 +55,25 @@ describe TodoService, services: true do
         should_create_todo(user: admin, target: confidential_issue, author: john_doe, action: Todo::MENTIONED)
         should_not_create_todo(user: john_doe, target: confidential_issue, author: john_doe, action: Todo::MENTIONED)
       end
+
+      context 'when a private group is mentioned' do
+        let(:group) { create :group, :private }
+        let(:project) { create :project, :private, group: group }
+        let(:issue) { create :issue, author: author, project: project, description: group.to_reference }
+
+        before do
+          group.add_owner(author)
+          group.add_user(member, Gitlab::Access::DEVELOPER)
+          group.add_user(john_doe, Gitlab::Access::DEVELOPER)
+
+          service.new_issue(issue, author)
+        end
+
+        it 'creates a todo for group members' do
+          should_create_todo(user: member, target: issue)
+          should_create_todo(user: john_doe, target: issue)
+        end
+      end
     end
 
     describe '#update_issue' do