diff --git a/app/models/issue.rb b/app/models/issue.rb
index 576840843..34f02b300 100644
--- a/app/models/issue.rb
+++ b/app/models/issue.rb
@@ -22,6 +22,7 @@ class Issue < ApplicationRecord
   include Redmine::Utils::DateCalculation
   include Redmine::I18n
   before_validation :default_assign, on: :create
+  before_validation :force_default_value_on_noneditable_custom_fields, on: :create
   before_validation :clear_disabled_fields
   before_save :set_parent_id
   include Redmine::NestedSet::IssueNestedSet
@@ -2100,6 +2101,21 @@ class Issue < ApplicationRecord
     end
   end
 
+  # Forcefully set the default value to any custom field values which are not
+  # editable by the current user when creating a new issue. This may overwrite
+  # existing custom values of a copied issue which are not editable by the
+  # current user.
+  def force_default_value_on_noneditable_custom_fields
+    return unless custom_field_values_changed?
+
+    editable_custom_field_ids = editable_custom_fields(author).map(&:id)
+    custom_field_values.each do |field_value|
+      unless editable_custom_field_ids.include?(field_value.custom_field_id)
+        field_value.value = field_value.custom_field.default_value
+      end
+    end
+  end
+
   def filter_projects_scope(scope=nil)
     case scope
     when 'system'
diff --git a/test/unit/issue_test.rb b/test/unit/issue_test.rb
index 76189f681..5b286f264 100644
--- a/test/unit/issue_test.rb
+++ b/test/unit/issue_test.rb
@@ -1575,6 +1575,19 @@ class IssueTest < ActiveSupport::TestCase
     assert_equal 'relation', j.details[0].property
   end
 
+  def test_copy_should_only_copy_editable_custom_fields
+    cf = CustomField.find 1
+    cf.roles << Role.find(1)
+    cf.visible = false
+    cf.save!
+
+    User.current = User.find(3)
+    issue = Issue.new.copy_from(Issue.find(3))
+
+    assert issue.save
+    assert_equal '', issue.custom_field_value(1)
+  end
+
   def test_should_not_call_after_project_change_on_creation
     issue = Issue.new(:project_id => 1, :tracker_id => 1, :status_id => 1,
                       :subject => 'Test', :author_id => 1)