Phishingresistant

Phishingresistant authentication describes methods designed to resist phishing attacks by ensuring credentials cannot be stolen through fraudulent websites or deceptive domains. In practice, it refers to passwordless and multi-factor approaches that rely on public-key cryptography and origin-bound credentials, such as those enabled by FIDO2/WebAuthn. Security guidelines, including NIST SP 800-63, categorize certain authenticator implementations as phishingresistant when they cannot be phished or misused by an attacker.

How it works: For each relying party, the authenticator generates a unique public–private key pair. The private key remains on the user’s device; the service stores only the public key. During sign-in, the server issues a challenge that the authenticator signs with the private key. The signature is valid only for the origin that registered the credential, making it ineffective on a phishing site. This model often uses hardware security keys or platform authenticators and may require user verification (such as a fingerprint or PIN). It enables passwordless login and broad phishing resistance for web and mobile applications.

Adoption and limitations: Phishingresistant credentials are recommended for high-security accounts and enterprise deployments and are supported across many platforms, but may require compatible devices and services and can involve hardware costs. They are not a foolproof shield against all phishing, especially in cases of social engineering around legitimate sites or device compromise; they should be implemented as part of a layered security approach with recovery and backup considerations.