What term describes the hijacking/reuse of a magic cookie used for user authentication?

The term that describes the hijacking or reuse of a magic cookie used for user authentication is session hijacking. Session hijacking occurs when an attacker takes control of a user’s session by obtaining a valid session token, typically through methods such as network sniffing, cross-site scripting (XSS), or session fixation attacks. Once the attacker has the magic cookie, they can impersonate the legitimate user, gaining unauthorized access to that user’s session, and thus potentially sensitive information and functionalities.

In this scenario, "magic cookie" refers to a piece of data used to maintain an authenticated session, and if an attacker successfully hijacks that cookie, they can effectively take over the session. Understanding session hijacking is crucial for organizations to implement proper security measures such as session timeouts, secure cookie attributes (like HttpOnly and Secure flags), and using HTTPS to secure data in transit.