A security flaw was found in the way Plone, a user friendly and powerful content management system, previously protected user's cookie data in certain situations. A remote attacker could provide a specially-crafted URL that, when visited by a valid Plone user could lead to Plone user's cookie to be forwarded if the victim was using certain browsers (possibility of session hijack).
References: http://plone.org/products/plone/security/advisories/20130611-announcement
The CVE identifier of CVE-2013-4200 has been assigned to this issue: http://www.openwall.com/lists/oss-security/2013/08/01/2
Created plone tracking bugs for this issue: Affects: epel-5 [bug 991015]
The hotfix is available here: http://plone.org/products/plone-hotfix/releases/20130618