Phishing-Resistant MFA
¿Qué es Phishing-Resistant MFA?
Phishing-Resistant MFAMFA methods that cryptographically bind authentication to the legitimate web origin — FIDO2/WebAuthn passkeys, smart cards, and Windows Hello — rendering AiTM proxy phishing, MFA fatigue, and OTP interception ineffective.
Phishing-resistant MFA is the category of authentication methods that cannot be intercepted, replayed, or tricked into authorizing the wrong relying party. The canonical examples are FIDO2 / WebAuthn (security keys, platform passkeys on Apple, Android, and Windows), PIV smart cards, and Windows Hello for Business. All of them share the same security property: the authenticator only generates a signature for the specific RP-ID (origin) it is presented with, so a credential registered with `login.example.com` cannot be coerced into signing a challenge from `login-evil.example.com`, even via a transparent AiTM proxy. They also defeat the lesser-but-common attacks that still work against TOTP and push-based MFA — MFA fatigue, push bombing, OTP-relay phishing kits (EvilProxy, Tycoon, Evilginx) — because there is no human-typed or human-tapped artifact for an attacker to relay. Major U.S. and European regulators (CISA, OMB M-22-09, ENISA, U.K. NCSC) have moved from 'use MFA' to 'use phishing-resistant MFA' guidance, and many enterprises now require it for privileged accounts and for any user accessing federated cloud services.
● Ejemplos
- 01
A bank requires hardware FIDO2 keys for all admin users, eliminating the AiTM-phishing risk that previously affected TOTP and push-MFA accounts.
- 02
U.S. Executive Order 14028 and OMB M-22-09 push federal civilian agencies to phishing-resistant MFA for all interactive logins by 2024.
● Preguntas frecuentes
¿Qué es Phishing-Resistant MFA?
MFA methods that cryptographically bind authentication to the legitimate web origin — FIDO2/WebAuthn passkeys, smart cards, and Windows Hello — rendering AiTM proxy phishing, MFA fatigue, and OTP interception ineffective. Pertenece a la categoría de Identidad y acceso en ciberseguridad.
¿Qué significa Phishing-Resistant MFA?
MFA methods that cryptographically bind authentication to the legitimate web origin — FIDO2/WebAuthn passkeys, smart cards, and Windows Hello — rendering AiTM proxy phishing, MFA fatigue, and OTP interception ineffective.
¿Cómo funciona Phishing-Resistant MFA?
Phishing-resistant MFA is the category of authentication methods that cannot be intercepted, replayed, or tricked into authorizing the wrong relying party. The canonical examples are FIDO2 / WebAuthn (security keys, platform passkeys on Apple, Android, and Windows), PIV smart cards, and Windows Hello for Business. All of them share the same security property: the authenticator only generates a signature for the specific RP-ID (origin) it is presented with, so a credential registered with `login.example.com` cannot be coerced into signing a challenge from `login-evil.example.com`, even via a transparent AiTM proxy. They also defeat the lesser-but-common attacks that still work against TOTP and push-based MFA — MFA fatigue, push bombing, OTP-relay phishing kits (EvilProxy, Tycoon, Evilginx) — because there is no human-typed or human-tapped artifact for an attacker to relay. Major U.S. and European regulators (CISA, OMB M-22-09, ENISA, U.K. NCSC) have moved from 'use MFA' to 'use phishing-resistant MFA' guidance, and many enterprises now require it for privileged accounts and for any user accessing federated cloud services.
¿Cómo defenderse de Phishing-Resistant MFA?
Las defensas contra Phishing-Resistant MFA combinan habitualmente controles técnicos y prácticas operativas, como se detalla en la definición.
¿Cuáles son otros nombres para Phishing-Resistant MFA?
Nombres alternativos comunes: FIDO2 MFA, Origin-bound MFA.
● Términos relacionados
- identity-access№ 458
FIDO2
Estándar abierto de autenticación de la FIDO Alliance que combina WebAuthn (API del navegador) y CTAP (protocolo del autenticador) para un inicio de sesión sin contraseña y resistente al phishing.
- identity-access№ 1359
WebAuthn
API JavaScript estándar del W3C que permite a las aplicaciones web registrar y autenticar usuarios mediante credenciales de clave pública en autenticadores de plataforma o externos.
- identity-access№ 888
Passkey
Credencial FIDO2/WebAuthn resistente al phishing: un par de claves asimétricas ligado al dispositivo o sincronizable que sustituye la contraseña por un desafío-respuesta criptográfico.
- identity-access№ 793
Autenticación multifactor (MFA)
Método de autenticación que requiere dos o más factores independientes —normalmente de categorías distintas— antes de conceder acceso.
- identity-access№ 750
Fatiga de MFA (Push Bombing)
Ataque en el que el adversario, con la contrasena valida, inunda a la victima de notificaciones push de MFA hasta que esta aprueba una por confusion o cansancio.
- identity-access№ 1309
U2F (Universal 2nd Factor)
Estándar abierto de autenticación de la FIDO Alliance que añade un segundo factor hardware a la contraseña mediante una llave de seguridad USB, NFC o Bluetooth.