Stopping Credential Stuffing with Login Velocity and Device Context

Credential stuffing tries leaked username/password pairs against your login API until one works. It is not the same as brute force (guessing one account) and it is not KYC. The event that matters is user.login: customer id when known, device fingerprint, IP, session id, and success/failure.

Stuffing looks like many failures across identifiers, then a success on a new device. Write the rule as identifier + action + window + threshold. Pair IP reputation and VPN detection with device novelty. Do not BLOCK every new phone. REVIEW or step-up until a fingerprint or IP is listed.

MFA is not telemetry

Attackers stuff accounts that lack MFA. You still need the login event so support can explain a challenge. Store the fraud event id next to the session.

Naiza evaluates login events with velocity rules and device intelligence. Product copy describes blocking stuffing and brute force in real time—confirm fields in the docs. Read credential stuffing, velocity checks, IP reputation, VPN detection, and account takeover.

Use ALLOW, REVIEW, BLOCK without a black box when you promote a shadow rule to enforcing.