Common Vulnerabilities and Exposures assigned an identifier CVE-2008-1394 to the following vulnerability: Plone CMS before 3 places a base64 encoded form of the username and password in the __ac cookie for all user accounts, which makes it easier for remote attackers to obtain access by sniffing the network. References: http://www.securityfocus.com/archive/1/archive/1/489544/100/0/threaded http://www.procheckup.com/Hacking_Plone_CMS.pdf http://plone.org/about/security/overview/security-overview-of-plone/
Fedora Project does not consider this a security issue. For secure communication over HTTP, SSL/TLS should be used.