Cookies become a security threat when hackers get access to them. If hackers hijack your cookies, they can get access to your session, your passwords and other related online activities. Hackers sometimes create “Super Cookies” and “Zombie cookies” to steal information from authentic cookies. Such cookies are difficult to identify and delete and sometimes work like worms replicating themselves, thus making it more difficult to get rid of them. Hackers can also steal your cookies if they get access to your network or to the server of the website you are visiting. For example, if your bank’s or shopping website’s server was hacked into, chances are, the hacker has access to your cookies and thereby all your account details.