What Is Phishing-Resistant MFA?

Understanding Phishing and Its Threats 

Phishing is still one of the most common and dangerous forms of online attacks. Hackers use it to trick people into giving away personal information, like usernames, passwords, or credit card details. These attacks usually come through emails that look like they’re from someone you know or trust. The emails contain links that take you to fake websites designed to steal your information. Even though more people are aware of phishing, it remains a big problem because attackers keep finding new ways to get around basic security measures.

Now, more than ever, companies need to adopt new and stronger security strategies to protect their sensitive data. Multi-factor authentication (MFA) has become essential. The extra layers of security it provides have been shown to greatly lower the chances of a successful attack or unauthorized access. But not all MFA methods are equally effective. Traditional MFA, like using one-time passwords (OTPs) sent through texts, helps to an extent, but it’s still vulnerable to advanced phishing techniques.

OTPs, or one-time passwords, are short codes sent to you when logging in, usually via text or a mobile app. These codes are created with cryptographic algorithms and change each time you log in. While OTPs add another layer of protection, they can still be intercepted or tampered with. That’s why phishing-resistant MFA is becoming more important—it offers a much stronger defense against these attacks.

What Makes MFA Phishing-Resistant

Not every second factor qualifies as phishing-resistant. The distinction matters and it is not a marketing label.

Legacy MFA adds a step to the login process. But if that step produces a value that can be intercepted and forwarded in real time, the attack still succeeds. The extra step exists. The attacker steps around it.

Phishing-resistant MFA works differently. Authentication is bound to a specific domain and a specific device. When a user attempts to log in, the credential that proves their identity is generated for that origin and only that origin. A phishing site operating on a different domain cannot produce a valid challenge. A relay attack cannot forward one that resolves correctly. There is nothing to intercept.

The technical standard that defines this is FIDO2. Any authentication factor that meets FIDO2, including hardware security keys, passkeys stored in a device secure enclave and biometric authenticators bound to a physical token, qualifies as phishing-resistant. SMS codes, time-based OTPs and push notifications do not, regardless of how they are positioned.

Why SMS Codes and Push Notifications Don’t Qualify

SMS codes, time-based OTPs and push notifications are widely deployed. They are described as MFA. They are not phishing-resistant.

The reason is the relay attack. A phishing site captures credentials and passes them to the real login portal in real time. The real portal triggers an MFA challenge. The phishing site mirrors that challenge back to the victim. The victim responds. The attacker forwards the response. The portal authenticates the session.

The exchange takes seconds. The code is valid. The login is legitimate. The victim sees nothing wrong. The attacker has full access.

This works because SMS codes and OTPs have a transferable value. They can be read, relayed and consumed. Push notifications present a challenge the user approves without verifying which site generated it. Neither factor is bound to the site the user thinks they are logging into. That binding is exactly what phishing resistance requires.

FIDO2 and WebAuthn

FIDO2 is the standard that defines phishing-resistant authentication. WebAuthn is the web API component of FIDO2. Together they define how credentials are created, stored and used in a way that cannot be phished.

When a user registers with a FIDO2-compliant service, the authenticator generates a key pair. The private key is stored on the device and never leaves it. The public key is sent to the server.

During login, the server issues a challenge. The challenge is bound to the exact domain the user is authenticating to. The authenticator signs the challenge with the private key. The server verifies the signature against the public key.

A phishing site cannot produce a valid challenge for a domain it does not control. A relay attack cannot forward a challenge that resolves to the wrong origin. The authentication fails before the attacker captures anything useful.

FIDO2-compliant authenticators include hardware security keys, passkeys stored in a platform secure enclave and biometric devices that bind the private key to a physical token. All inherit this binding property.

FIDO Security Keys

What are FIDO Security Keys?

FIDO security keys are small devices that help that help protect against phishing attacks. They follow the guidelines set by the FIDO (Fast Identity Online) Alliance, which focuses on making secure and easy-to-use login methods. Instead of relying on passwords or one-time codes, these keys use advanced technology, making it much harder for hackers to break in.

How FIDO Security Keys Work

When you set up a FIDO security key with a service, it creates two cryptographic keys: one key, the private key and another one the public key. The private key stays on your device, and the public key is stored by the service you’re using.

When you log in, the service sends a challenge, including a one-time number called a nonce. This nonce prevents attackers from using old data to get in. Your browser takes this challenge and turns it into a client data hash, which is sent to the FIDO security key.

The security key checks the client data hash. If it matches, the key uses the private key to sign the challenge and send it back to the service, confirming your identity. If the client data hash doesn’t match (for example, during a phishing attack), the key won’t recognize it, and the login is blocked. This process ensures strong phishing resistance by preventing attackers from tricking the system.

By combining the service, the browser, and the FIDO security key, this method creates a strong chain of trust. The FIDO key ensures that your login is secure, even if someone tries to intercept your data.

FIDO security keys are great at stopping phishing because they don’t use passwords or other personal details that can be easily stolen. Even if someone gets the public key, they still can’t log in without the private key, which stays safely stored on your device.

These keys are also user-friendly and work with both computers and mobile devices. They connect through USB, NFC, or Bluetooth and integrate seamlessly into existing systems. Since FIDO security keys follow widely accepted standards like FIDO2 and WebAuthn, they offer a consistent, secure login experience across many platforms and services.

Biometric Authentication

What is Biometric Authentication?

Biometric authentication uses biological characteristics to verify an individual’s identity. These could be fingerprints, facial features, iris patterns, and voice recognition for example, making it a highly secure form of authentication crucial to modern authentication systems. These traits are tied to each person and, as a form of multifactor authentication (MFA), they offer a high level of security and convenience crucial to modern authentication systems. Biometric authentication means capturing a trait sample. This sample is then converted to a digital template and securely stored for future access. Only when a sample matches the stored template will access be authorized.

How Biometric Authentication Works

The fundamental basis of the security of biometric systems rests on the suitably unique and stable biometric trait. They provide a secure access point because the trait used in the biometric system is unique to that individual. No two people have the exact same fingerprint, and a fingerprint is stable over time. It does not change significantly from day to day or from year to year, which makes it a reliable identification method. A fingerprint is not easily replicated.

Many devices, such as laptops, smartphones, and smart rings, now support biometric authentication. These devices often use push notifications to prompt users during the authentication process. Most devices come equipped with biometric sensors, which, together with the current level of sensor technology, make it relatively easy and straightforward to incorporate biometrics into a multifactor authentication strategy.

Among the various biometric authentication methods, fingerprint recognition is by far the most common. At the same time, facial recognition—a method that employs a person’s distinctive facial features—is rapidly catching up. Other less common, but high accuracy biometric methods, include iris and retina scans, which analyze the unique patterns in the iris or retina; and voice recognition, which uses the unique vocal characteristics and speech patterns of a person to enable secure voice-based authentication.

Biometric Authentication: Challenges and Considerations

Biometric authentication has many advantages; however, one of its main disadvantages is privacy concerns. Biometric data is probably the most sensitive data we own. If our fingerprint is compromised, we cannot simply obtain a new fingerprint, as we would with a password. Biometric data is so rich and unique that we must make certain that it is stored securely. If possible, this data should remain under our control.

Another issue is the accuracy of biometric systems. There are certain conditions that affect identity verification methods, like lighting for facial recognition.

Biometric data is, however, becoming more and more popular and comprehensive phishing-resistant security solutions are emerging from the combination of biometrics and other powerful authentication strategies like FIDO security keys.

The Future of Biometric Authentication

Biometric authentication, offering both security and convenience, is expected to be a key part of future phishing-resistant systems. As technology advances, biometrics will play a bigger role in protecting against cyber threats, providing a strong and reliable defense.

Solution providers are certain that biometric authentication will continue to be a much better solution a for local authentication than passwords and similar knowledge-based authentication solutions, which have become far too easy for hackers to compromise, socially engineer, and phish.

Smart Cards 

While we’re on the topic of phishing-resistant multi-factor authentication, it makes sense to mention Smart cards. These are another form of phishing-resistant multi-factor authentication but only if combined with other knowledge-based forms of authentication. An embedded microprocessor chip is at the heart of smart cards. This chip can process data and store it securely.

Much like an access card, these cards require physical possession to authenticate, controlling physical access to secure areas and making them resistant to phishing scams. It’s important to note that organizations need to be clear about how these smart cards are managed and protected to ensure their effectiveness in securing both digital and physical environments.

Types of Smart Cards

• Contact-based smart cards: The chip must connect with the card reader for the two to work together.
• Contact-less Smart Cards: A tiny antenna lets a contactless smart card access a reader. The reader recognizes that there is a card present, and it sends a request for information stored on the card.

How Smart Cards Work

Smart cards are very secure because they can store cryptographic keys and handle secure data exchanges. The data on the card is heavily encrypted, making it really hard for anyone unauthorized to access or tamper with it.

Presenting a smart card with any sort of antenna to a reader will help make the reader secure. In part, this is because various elements within any antenna serve as tiny electromagnetic puzzle pieces that help the reader figure out what it is and what it can do.

When a smart card and a reader have a conversation, they work together to ensure that the smart card is the only one that can speak that particular “language.”

Compared with similar devices, smart cards are much more versatile. You can use them for anything from accessing a building and computer network, to payment systems and government IDs. Because of this broad range of uses, they’re a popular choice for organizations that require a variety of different security applications. Smart cards do a decent job at protecting against phishing attacks, as attackers would find it extremely difficult to replicate or intercept the data as they would need the card itself. Smart cards are exceptionally durable and cost-effective. They’re also highly dependable. Overall, they carry out a system’s security functions in a reliable way for a long time.

Smart cards that require contact must be inserted into a reader that is physically connected to the system in some way. They are used in applications such as credit cards, SIM cards, and secure access systems.

Contactless smart cards operate in much the same way but communicate with the reader via radio waves, without any necessary physical contact. They are often used in public transportation systems, secure access, and payment solutions.

Because of the way they are used and the way they are designed, smart cards represent a secure, generalized solution to the wide variety of identification and access control tasks faced by any organization, public or private.

Future Trends in Smart Card Technology

The future looks promising for the smart card and its technology will continue to advance. We’ll continue to see developments such as contactless developments and integrations with other types of security methods.

Deploying Phishing-Resistant MFA in an Enterprise

Deploying phishing-resistant MFA is not just a technology decision. It requires choices about authenticator type, policy enforcement and user rollout.

The authenticator choice depends on the environment. Hardware security keys work across any device, require no software installation and are the most broadly compatible option. Passkeys stored in a platform secure enclave are increasingly viable as operating system support improves but depend on the device ecosystem. Biometric authenticators bound to a dedicated hardware device offer the highest assurance level and remove dependency on the user’s personal hardware.

Policy enforcement matters as much as the authenticator. Conditional access policies should require phishing-resistant MFA for all privileged access, remote sessions and applications handling sensitive data. Enforcing at the identity provider level means the requirement applies regardless of which application the user is accessing.

User rollout is where most deployments stall. Moving from a push notification to a hardware key or biometric device is a physical change. Distributing devices, preparing IT support and establishing a clear process for lost or damaged hardware before launch is not optional.

Why Phishing-Resistant MFA is Crucial

Cyber threats are becoming more advanced, and phishing is still one of the easiest ways for attackers to steal things like passwords or financial info, usually through fake emails. As these attacks get smarter, it’s more important than ever for people and organizations to improve their security. MFA plays a big role in this by adding an extra layer of protection that makes it harder for hackers to get in.

One of the best ways to guard against phishing is by using phishing-resistant MFA. Traditional login methods are only safe as long as your password or PIN stays secret. But attackers have figured out ways, like MFA bypass attacks, to get around these methods. They use fake emails, bogus websites, or even malicious versions of trusted software to trick you into giving up your login details. With phishing-resistant MFA, even if your password or PIN is stolen, hackers won’t be able to use it.

Newer technologies, like FIDO2 and biometric authentication, offer better protection. The Token Smart Ring is a great example, combining both methods to provide even stronger security.

While deploying phishing-resistant MFA is crucial, many organizations still experience breaches, even when they try to use basic MFA. Reports from the Cybersecurity and Infrastructure Security Agency show that many companies aren’t using MFA effectively, leaving them open to attacks.

Implementing Phishing-Resistant MFA with Token's Next-Generation Smart Ring

The TokenCore™ Wearable is an innovative solution that combines everything you need for strong protection against phishing and ransomware attacks into one wearable device. The Token smart ring includes:

• FIDO Authentication: Incorporating FIDO security keys and FIDO2 protocols for strong, phishing-resistant authentication.
• Biometric Authentication: Utilizing biometric methods for additional layers of security.
• Dongle-Like Functionality: Offering hardware-backed security like dongles but in a convenient, wearable form.
• Smart Device Security: Storing biometrics and cryptographic keys securely within the ring itself.

The TokenCore™ Wearable makes phishing-resistant MFA easy and secure by combining advanced security features. No need for multiple devices or complicated steps—just tap your finger on the ring to log in safely, without worrying about phishing.

Request a demo today and see how Token’s Next-Generation MFA can secure your organization from phishing and ransomware attacks with ease and simplicity.

FAQ