Plone 3.3.1 __ac cookie and security

eras mus <[email protected]> Thu, 28 May 2015 17:56:36 +0530
Newsgroups gmane.comp.web.zope.plone.user
Message-ID <CALeO_hMB9C05gNh6fAdkNv+s9BKZPz-4-_HKTiGnnRuX3D+4rA@mail.gmail.com>
Hi,

In an old Plone 3.3.1 during security audit the following was done.

After logging in from login form ,the cookie __ac was captured .
Then logged out. The logged out message got displayed  on the page.
Now after injecting the same cookie value in the browser , When site
is accessed it is showing as logged in.

It is a security threat isn't ? Someone can capture the __ac value and log in.

How to overcome this ?(without upgrading to new plone version)
Please give your valuable suggestions.

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