Account Takeover Account takeover is the moment the attacker gains full control of an account — not only access, but the ability to change the password, the recovery mail address, the phone number and the second factor, while the real owner is shut out with no technical way back in on their own. Takeover is rarely the first stage of an attack. It is usually the destination of what came before: phishing, credential stuffing, token theft.

Authentication Bypass An authentication bypass means the attacker reaches a protected part of the system without logging in the ordinary way. They need not know a password. Sometimes a flaw in the logic is enough, or an unprotected endpoint, a predictable token, a misconfigured proxy, or a gap between two steps of the login.

Kerberoasting Kerberoasting is an attack specific to Windows domain networks and Active Directory (AD). User logins are handled by the Kerberos protocol, which issues tickets as proof of identity. In a domain environment there are non-user accounts — service accounts — under which most background tasks and services run, such as databases and business applications. Service accounts are set up so that any user can request a ticket for access to a given service. The catch is that the ticket is encrypted with the service account's password.

Pass-the-Hash So that it does not keep the password in readable form, Windows remembers its cryptographic fingerprint — the hash. With older Windows authentication (NTLM), the password is not required to prove identity; the hash is enough. Pass-the-hash abuses exactly that: if the attacker obtains a user's hash, they can log in with it without ever learning the real password.

Session Hijacking When you log in, the service opens a session — a state that remembers you are you, together with everything that goes with it, such as your preferences and settings. The main benefit is that you do not have to type a password every few minutes as you move through the features. That session is marked by an identifier, usually held in a browser cookie. Session hijacking is the taking over of a session that is already open. The attacker does not attack the login; they slip into a session that has already passed authentication and carry on operating the service in your name.

Token Theft A token is proof that you have already logged in. When you sign in and confirm your identity with a second factor, the service issues a token, stored in the browser, which vouches that you have already been checked the next time round. The token is sent automatically with every further request, so you do not have to type the password again. Token theft is the taking of that proof. With it in hand, the attacker presents themselves as you — without your password and without the second factor, because both have already been approved.