diff --git a/spec/ruby/core/dir/for_fd_spec.rb b/spec/ruby/core/dir/for_fd_spec.rb
index eeda26754a..b2af7bda84 100644
--- a/spec/ruby/core/dir/for_fd_spec.rb
+++ b/spec/ruby/core/dir/for_fd_spec.rb
@@ -1,6 +1,7 @@
 require_relative '../../spec_helper'
 require_relative 'fixtures/common'
 
+quarantine! do # leads to "Errno::EBADF: Bad file descriptor - closedir" in DirSpecs.delete_mock_dirs
 ruby_version_is '3.3' do
   guard -> { Dir.respond_to? :for_fd } do
     describe "Dir.for_fd" do
@@ -75,3 +76,4 @@ ruby_version_is '3.3' do
     end
   end
 end
+end