FIDO Device Security & Cryptographic Operations

Question 1

What is the primary goal of device security in FIDO authentication?

Accepted Answer

To secure authenticator operations

Answer

The primary goal of device security in FIDO authentication is to protect the operations of the authenticator itself. This involves safeguarding the cryptographic keys and the processes that use them, ensuring they cannot be compromised or tampered with. By securing the authenticator, FIDO prevents unauthorized access and ensures the integrity and trustworthiness of the entire authentication process.

Question 2

Which cryptographic method is central to FIDO authentication?

Accepted Answer

Public key cryptography

Answer

Public key cryptography, also known as asymmetric cryptography, is central to FIDO authentication. This method uses a pair of mathematically linked keys—a public key and a private key—where the private key is securely stored on the user's device and never leaves it. This architecture allows for strong, phishing-resistant authentication by signing challenges with the private key, which can then be verified by the public key.

Question 3

How is a private key stored in a secure authenticator?

Accepted Answer

Within secure hardware

Answer

In FIDO authentication, the private key is stored within secure hardware on the user's device, such as a Trusted Platform Module (TPM) or a secure element. This hardware-based storage provides a high level of protection against software attacks and physical tampering. Keeping the private key isolated and protected ensures it cannot be easily extracted or copied, which is fundamental to FIDO's security model.

Question 4

What operation uses the private key during authentication?

Accepted Answer

Signs the challenge

Answer

During FIDO authentication, the private key is used to digitally sign a challenge issued by the relying party (server). This signing operation proves possession of the private key without ever revealing the key itself. The server then uses the corresponding public key to verify the signature, confirming the user's identity and the authenticity of the device.

Question 5

What prevents a cryptographic key from being copied or exported?

Accepted Answer

Bound to secure hardware

Answer

A cryptographic key is prevented from being copied or exported in FIDO by being securely bound to the hardware authenticator. This means the key is generated and stored within a secure element or TPM, designed to resist extraction and duplication. This hardware binding ensures that the private key never leaves the device, making FIDO authentication highly resistant to phishing and credential theft.

(FIDO) FIDO Certified Authenticator Practice Test

(FIDO) FIDO Certified Authenticator Practice Test

FIDO Device Security & Cryptographic Operations