Passwordless Authentication with Passkeys

Many security breaches happen because attackers steal or guess user passwords. These passwords are often reused, easy to guess, or exposed through phishing. As a result, systems that rely on passwords face ongoing risks from credential theft and account takeovers.

To fix this problem, many systems are moving to passwordless authentication with passkeys. Passkeys remove the need to type or store passwords and use cryptographic keys that are safer and easier to manage. This article explains what passkeys are, how passwordless authentication works with them, and where they offer the most value.

What Are Passkeys?

Passkeys are digital credentials that are used to log in to an account without a password. A passkey is made of a public key and a private key. The public key is saved by the service or website, and the private key stays safely on the user’s device.

Passkeys work with a device and usually need a fingerprint, face scan, or PIN to unlock. They are based on public key cryptography and are not shared or typed during login.

What is Passwordless Authentication?

Passwordless authentication is a way to log in without entering a password. It uses something the user has, like a device with a passkey, or something the user is, like a fingerprint or face.

The system checks identity using cryptographic methods or biometric data instead of a stored password. This helps prevent common attacks like phishing and password theft.

Benefits of Using Passkeys for Passwordless Authentication

1. Protection Against Phishing and Credential Theft

Passkeys protect users from phishing and credential theft because they are never typed or shared. The private key used to sign the login request stays inside the user’s device and cannot be stolen through fake websites or email links. This stops attackers from using the most common method of stealing passwords.

2. Elimination of Password Fatigue and Resets

Users do not have to remember or reset passwords when using passkeys. This removes the common problem of password fatigue, where people forget or reuse passwords across services. It also reduces the number of password reset requests, which can burden support teams.

Logging with passkeys takes less time and fewer steps. A user can unlock access by using a fingerprint, face scan, or a trusted device. There is no need to enter or confirm passwords. This makes the login process faster and easier without lowering security.

4. Stronger Alignment with Zero Trust Models

Passkeys support Zero Trust models by removing the need for standing credentials. Since each login request is verified through a cryptographic challenge, identity is confirmed every time. This fits the Zero Trust principle that no user or device should be trusted without verification.

5. Compliance with Security Standards and Regulations

Passkey-based authentication helps meet compliance requirements under frameworks like NIST, GDPR, and others. These standards prefer methods that avoid static passwords and reduce the chance of data breaches. Passkeys meet this requirement by offering secure identity proof without exposing secrets.

To explore more on this topic, see Advantages of Passwordless Authentication for Businesses.

How Passwordless Authentication Works with Passkeys

1. Public and Private Key Cryptography Explained

Passkeys are based on a cryptographic system called public key cryptography. This system uses two keys that are linked but not the same. One key is called the public key, and the other is the private key. The public key is shared with the server or application. The private key stays safe inside the user’s device.

When a person wants to log in, the server sends a request. The user’s device uses the private key to answer this request. The server checks if the answer matches the public key. If it does, access is granted. This proves the identity of the user without sending or storing any passwords. The private key never leaves the device and is not exposed during the process.

2. Device-Based Storage and Biometric Confirmation

The private key in a passkey is stored inside the user’s personal device. This storage is handled by secure hardware parts like the Trusted Platform Module or Secure Enclave. These protect the private key from being copied or accessed by other software.

To use the private key, the user must confirm identity through a method like a fingerprint, a face scan, or a device PIN. This step is called biometric confirmation. It ensures that even if someone else gets the device, they cannot use the passkey without passing this check. The combination of secure storage and biometric checks makes passkeys both safe and easy to use.

3. FIDO2 and WebAuthn Protocols Behind the Flow

FIDO2 and WebAuthn are two protocols that make passkeys work across different browsers and systems. FIDO2 defines how devices should store keys and confirm identity. WebAuthn is the part that works with browsers and websites to carry out the login process.

When a user signs up or registers a passkey, the system uses these protocols to create and store the public key and private key securely. During login, the server uses WebAuthn to talk to the device, which then uses FIDO2 to handle the key operations.

This setup allows passkeys to be used on different devices, systems, and applications without needing a separate password for each one.

4. Challenge–Response Mechanism in Action

When a user tries to log in, the server creates a one-time challenge. This is a short string of random data. The user’s device takes this challenge and signs it using the private key. This signed message is sent back to the server.

The server checks the signature using the public key it already has. If the signature is correct, it proves the user has the right private key without ever showing it. This process is called challenge-response. It is secure because the challenge cannot be reused, and the private key stays hidden during the entire process.

To learn how this process can be applied in real systems, see How to Implement Passwordless Authentication in Your Organization with SSH Communications Security.

Authentication Use Cases Where Passkeys Offer the Most Value

1. Cloud and Remote Access Management

Passkeys are useful for cloud and remote access because they allow users to log in from anywhere without needing to type or manage passwords. This makes it easier and safer to access cloud platforms and services using a trusted device.

The private key stays on the device and cannot be stolen through phishing or copied through remote attacks.

In remote access setups, passkeys help verify the identity of the user and the device. This ensures that only trusted users with approved devices can connect to cloud systems. It also reduces the risk of stolen credentials being used from unknown locations.

2. Privileged Access for Admins and Developers

Admins and developers often have access to sensitive systems. Using passkeys helps limit the risk of password misuse or theft. When passkeys are used, each authentication is verified using a private key that is stored safely in the user’s device.

This method supports role-based controls and reduces the attack surface. Even if someone tries to target a high-level account, they cannot log in without the correct device and biometric confirmation. This improves security for critical systems and data.

3. End-User Authentication Across Devices

Passkeys allow end users to log in across different devices without creating new passwords for each one. When the same passkey is available through a synced account or secure transfer method, users can access services on phones, laptops, or desktops using the same secure method.

This makes it easier to manage access in organizations where people use more than one device. It also keeps login consistent and secure across platforms without depending on password reuse.

Experience Passwordless Authentication with Passkeys Through SSH Solutions

SSH offers secure access solutions that support passwordless authentication with passkeys. These solutions remove the need for static credentials and allow organizations to use public key cryptography and biometrics for identity verification. SSH solutions are designed to help enterprises control access, reduce risk, and meet compliance requirements by using passkeys across IT, cloud, and operational environments.

PrivX enables just-in-time access based on Zero Trust principles and supports passkey-based and keyless authentication methods. For OT and MSP environments, SSH offers specialized editions of PrivX to control multi-tenant or industrial access. The Universal SSH Key Manager helps automate SSH key discovery and migration to passwordless models. Tectia SSH and NQX products support post-quantum encryption and secure access for mainframes, networks, and sensitive data flows.

Get a Demo or Trial of any SSH solution, including PrivX, UKM, Tectia, or NQX, to experience passwordless authentication with passkeys in action.

FAQ

1. What are passkeys, and how do they work?

Passkeys are digital keys that let you log in without a password. They use a public key saved by the website and a private key stored on your device. Only your device can respond to a login request using the private key.

2. Are passkeys more secure than traditional passwords?

Yes. Passkeys cannot be stolen through fake websites and are not reused. The private key never leaves your device, making it safer than passwords.

3. How do passkeys enhance passwordless authentication?

Passkeys remove the need to type or manage passwords. You just use your device and confirm with a fingerprint, face scan, or PIN.

4. Can passkeys be used across multiple devices and platforms?

Yes. Passkeys can be used on phones, laptops, or tablets. Some systems allow secure syncing of passkeys between devices.

5. How can organizations implement passkeys for passwordless authentication?

Organizations need to support login systems that use public key cryptography and allow devices to handle authentication using passkeys.