Passwordless authentication replaces passwords with biometrics, magic links, or cryptographic tokens. Done right, it reduces phishing risk and stops credential stuffing. Done wrong, it can open the door to privilege escalation—an attacker moving from a low-privilege account to full administrative control without ever typing a password.
The most common causes are weak identity verification during sign-up, poor session management, and missing authorization checks on protected endpoints. If your token issuance logic trusts too much, any flaw in API-level privileges becomes an open highway. Attackers use token replay, ID spoofing, or misconfigured role binding to unlock restricted functions.
Privilege escalation in a passwordless system often happens because the authentication layer and authorization layer are not tightly coupled. If identity is granted without a password, the authorization checks must be airtight. Missing the link between “who” and “what they can do” is where the compromise lives.