Glossary
Account Takeover (ATO)
An attack in which a third party gains control of a user's legitimate account through credential theft, credential stuffing, an authentication flaw, or session hijacking. In an your product product, an account takeover opens access to payslips, bank details, and personal data. MFA and anomalous-login detection are the primary defenses.
The most common paths to takeover
Credential stuffing replays email/password pairs from previous breaches, betting on reuse. Phishing captures credentials directly, sometimes the MFA code in real time. Application flaws — poorly designed password reset, predictable session tokens, no rate limiting on login — provide purely technical paths. In a product, a single compromised admin account exposes every employee.
Defending accounts in an application
MFA — ideally via passkey or app, not SMS — blocks most stolen-credential attacks. It must be paired with rate limiting and anomalous-login detection (new country, new device), a password policy checked against breach databases, and short-lived, revocable sessions. An audit verifies these protections hold against a real attacker, not just on paper.
Frequently asked questions
Is MFA enough to prevent account takeover?
It eliminates most attacks based on stolen credentials, but not all: real-time phishing and MFA fatigue can bypass it. Passkeys (WebAuthn) resist phishing and are the most robust protection currently available.
How do you detect an ongoing takeover?
By monitoring anomaly signals: login from a new country or device, email or password change followed by sensitive actions, spikes in login attempts. Alerting the user and requiring re-authentication on these events sharply limits the impact.