Plone 2.5 through 2.5.4 and 3.0 through 3.0.2 allows remote attackers to execute arbitrary Python code via network data containing pickled objects for the (1) statusmessages or (2) linkintegrity module, which the module unpickles and executes.
Unspecified vulnerability in PlonePAS in Plone 2.5 and 2.5.1, when anonymous member registration is enabled, allows an attacker to "masquerade as a group."