Authentication Failures

Overview

Authentication Failures are unsuccessful, invalid, interrupted, or suspicious attempts to prove identity or control of an authenticator, account, device, key, or session. The control exists to ensure that only appropriately identified and authorized principals can access resources or approve actions at the required level of assurance. They include ordinary user mistakes and malicious activity, so a failure count alone does not establish an attack. It should be interpreted alongside Adaptive Authentication because the concepts can affect the same decision without representing the same control, event, or risk.

The workflow establishes a trusted identity or service principal, binds authenticators, evaluates context, applies policy, and records the resulting access decision. Authorization must be enforced by the server or resource boundary on every relevant request and should not depend on hidden interface elements or untrusted client claims. In this context, monitoring should distinguish unknown accounts, bad secrets, expired tokens, blocked devices, failed step-up challenges, replay, recovery abuse, protocol errors, and service outages while protecting logs from unnecessary credential data.

It should connect the term to Phishing where that relationship changes access, transaction treatment, investigation, communication, or recovery.

Records should capture principal, authenticator or credential type, assurance level, resource, action, policy version, contextual signals, decision, failures, recovery, grants, revocations, and administrative changes. Sensitive secrets and authentication content should not be copied unnecessarily into logs.

Useful measures include enrollment and recovery success, challenge rate, failure rate, unauthorized attempts, privilege age, dormant access, review completion, false rejection, compromise events, and time to revoke access.

The relationship with Access Token should be documented where it affects residual risk or control ownership.