Products.CMFCore are the key framework services for the Zope Content Management Framework (CMF). The use of Python's marshal module to handle unchecked input in a public method on `PortalFolder` objects can lead to an unauthenticated denial of service and crash situation. The code in question is exposed by all portal software built on top of `Products.CMFCore`, such as Plone. All deployments are vulnerable. The code has been fixed in `Products.CMFCore` version 3.2.