Plone » Plone Cms » 2.5 beta2 : Security Vulnerabilities, CVEs,

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.

Plone CMS 3.0.5, and probably other 3.x versions, places a base64 encoded form of the username and password in the __ac cookie for the admin account, which makes it easier for remote attackers to obtain administrative privileges by sniffing the network.