Zope hotfix: Acquisition context checking
This hotfix addresses an important security issue that affects Zope version 2.3.0 and the current 2.3.1 beta 1 release.
The issue involves an error in the aq_inContextOf
method of objects
that support acquisition. A recent change to the access validation
machinery made this bug begin to affect security restrictions. The bug,
with the change to validation, made it possible to access Zope objects
via acquisition that a user would not otherwise have access to. This
issue could allow users with enough internal knowledge of Zope to
perform actions higher in the object hierarchy than they should be able
to.
We highly recommend that any Zope site running Zope 2.3.0 final or any alpha or beta version of 2.3.0 or 2.3.1 beta 1 have this hotfix product installed to mitigate the issue. Zope 2.3.1 beta 2 will contain a fix for the issue, at which time the hotfix can be removed. Zope versions prior to 2.3.0 are not affected by this issue.
http://www.zope.org/Products/Zope/Hotfix_2001-03-08/Hotfix_2001-03-08.tgz