GHSA-4hpj-8rhv-9x87 Products.CMFCore unauthenticated denial of service and crash via unchecked use of input with Python's marshal module

• PyPI Products.CMFCore: >= 3.0, < 3.2 → fixed in 3.2 • PyPI Products.CMFCore: < 2.7.1 → fixed in 2.7.1

Impact 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. Patches The code has been fixed in `Products.CMFCore` version 3.2. Workarounds Users can make the affected `decodeFolderFilter` method unreachable by editing the `PortalFolder.py` module in `Products.CMFCore` by hand and then restarting Zope. Go to line 233 of `PortalFolder.py` and remove both the `@security.public` decorator for `decodeFolderFilter` as well as the method's entire docstring. This is safe because the method is not actually used by current code. References • Products.CMFCore security advisory GHSA-4hpj-8rhv-9x87 Credits Thanks go to Nicolas VERDIER from onepoint. For more information If you have any questions or comments about this advisory: • Open an issue in the Products.CMFCore issue tracker • Email us at [email protected]