SSCP Cryptography — All Questions With Answers

Question 1

A security analyst is recommending a symmetric encryption algorithm for a new application that requires both confidentiality and authentication. Which algorithm and mode combination should they select?

Accepted Answer

AES-GCM. AES-GCM (Galois/Counter Mode) is a symmetric encryption algorithm that provides both confidentiality and authentication in a single, efficient operation. It combines AES encryption in counter mode with a Galois field-based message authentication code (GMAC), making it ideal for applications requiring both security properties.

Answer

3DES-CBC

Answer

AES-ECB

Answer

RC4

Question 2

An organization is implementing a digital signature solution to ensure non-repudiation of documents. Which combination of keys is used during the signing process?

Accepted Answer

Sender's private key to sign, sender's public key to verify. Digital signatures use asymmetric cryptography where the sender creates a signature with their private key, and the recipient verifies it with the sender's public key. This ensures non-repudiation because only the sender possesses their private key, so they cannot deny having signed the document. The process typically involves hashing the document and encrypting the hash with the sender's private key.

Answer

Recipient's public key to sign, recipient's private key to verify

Answer

Sender's public key to sign, recipient's private key to verify

Answer

A shared symmetric key for both signing and verification

Question 3

A company is deploying a VPN using IPsec. They want to ensure that even if the private key of the server is compromised, past session keys cannot be derived. Which key exchange method should they use?

Accepted Answer

Ephemeral Diffie-Hellman (DHE or ECDHE). Ephemeral Diffie-Hellman (DHE or ECDHE) provides perfect forward secrecy (PFS) because it generates a unique, temporary session key for each session using ephemeral key pairs. Even if the server's long-term private key is compromised, past session keys cannot be derived because they were created from ephemeral keys that are discarded after each session. This ensures that historical encrypted traffic remains secure.

Answer

Pre-shared key (PSK)

Answer

RSA key exchange

Answer

Diffie-Hellman with static keys

Question 4

A security administrator is configuring a web server to use TLS. They want to optimize performance while maintaining strong security. Which cipher suite should they prioritize?

Accepted Answer

TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384. Option D is correct because TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384 uses Elliptic Curve Diffie-Hellman Ephemeral (ECDHE) for perfect forward secrecy, ECDSA for efficient authentication, AES-256 in GCM mode for authenticated encryption, and SHA-384 for integrity. This combination provides the strongest security with modern, optimized algorithms, making it the best choice for performance and security on a TLS web server.

Answer

TLS_DHE_RSA_WITH_AES_128_CBC_SHA

Answer

TLS_RSA_WITH_AES_128_CBC_SHA256

Answer

TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256

Question 5

Which of the following hash algorithms is considered cryptographically broken and should be avoided due to collision attacks?

Accepted Answer

MD5. MD5 is known to have collision vulnerabilities and is no longer considered secure.

Answer

SHA-3

Answer

SHA-256

Answer

HMAC-SHA256

Question 6

An organization uses a PKI with a root CA that issues certificates to intermediate CAs, which then issue end-entity certificates. A client receives an end-entity certificate signed by an intermediate CA. During validation, which certificates are required to build the chain of trust?

Accepted Answer

End-entity certificate, intermediate CA certificate, and root CA certificate. In a PKI hierarchy, the chain of trust requires each certificate in the path to be validated up to a trusted root. The client must have the end-entity certificate, the intermediate CA certificate (to verify the end-entity's signature), and the root CA certificate (to verify the intermediate CA's signature). Without the intermediate CA certificate, the client cannot cryptographically link the end-entity to the root, breaking the chain.

Answer

Only the root CA certificate

Answer

Only the end-entity certificate and the root CA certificate

Answer

Only the end-entity certificate and the intermediate CA certificate

Question 7

A security engineer needs to choose an asymmetric algorithm for a system with limited computational resources, such as an IoT device. The algorithm must provide equivalent security to RSA 2048-bit while using smaller key sizes. Which algorithm should they choose?

Accepted Answer

Elliptic Curve Cryptography (ECC) with 256-bit keys. Elliptic Curve Cryptography (ECC) with 256-bit keys provides equivalent security to RSA 2048-bit because the elliptic curve discrete logarithm problem is significantly harder to solve than the integer factorization problem for the same key length. This allows ECC to achieve strong security with much smaller key sizes, making it ideal for resource-constrained IoT devices where memory, power, and processing are limited.

Answer

RSA with 2048-bit keys

Answer

Diffie-Hellman with 2048-bit keys

Answer

3DES with 168-bit keys

Question 8

A security auditor reviews a system that uses HMAC-SHA256 for message authentication. Which property does HMAC provide that a simple hash of the message does not?

Accepted Answer

Integrity and authentication using a shared secret. HMAC-SHA256 uses a shared secret key combined with the message before hashing, which provides both integrity (detecting tampering) and authentication (verifying the sender knows the secret). A simple hash of the message alone offers integrity but no authentication, because anyone can compute the same hash without a secret. Thus, HMAC adds authentication via the shared secret, making option C correct.

Answer

Confidentiality

Answer

Non-repudiation

Answer

Forward secrecy

Question 9

Which of the following is a secure protocol for remote administration of a server, replacing insecure protocols like Telnet?

Accepted Answer

SSH. SSH (Secure Shell) is the correct answer because it provides encrypted remote administration capabilities, replacing insecure protocols like Telnet that transmit data in plaintext. SSH uses public-key cryptography for authentication and symmetric encryption (e.g., AES, ChaCha20) for session confidentiality, protecting against eavesdropping and man-in-the-middle attacks.

Answer

FTP

Answer

HTTP

Answer

Telnet

Question 10

A company wants to implement a key management system. They need to generate cryptographic keys that are unpredictable. Which source of randomness should be used?

Accepted Answer

Hardware random number generator (HRNG). A hardware random number generator (HRNG) is the correct choice because it derives randomness from physical processes (e.g., thermal noise, quantum effects) that are inherently unpredictable and non-deterministic. Cryptographic key generation requires true entropy to resist brute-force and prediction attacks, which software-based deterministic methods cannot guarantee.

Answer

Random numbers from a website

Answer

Linear congruential generator (LCG)

Answer

Pseudorandom number generator (PRNG) seeded with current timestamp

Question 11

A certificate authority (CA) issues a certificate with the extended key usage (EKU) extension specifying 'serverAuth'. Which of the following is this certificate allowed to do?

Accepted Answer

Authenticate a TLS server. The Extended Key Usage (EKU) extension specifies the intended purpose of a certificate. The 'serverAuth' OID (1.3.6.1.5.5.7.3.1) explicitly permits the certificate to be used for authenticating a TLS server during the SSL/TLS handshake, such as in HTTPS. This is defined in RFC 5280 and is enforced by TLS clients to ensure the certificate is used only for its designated purpose.

Answer

Encrypt email

Answer

Sign code

Answer

Issue subordinate CA certificates

Question 12

Which of the following is a method to check the revocation status of a digital certificate in real-time without the client downloading a full list?

Accepted Answer

Online Certificate Status Protocol (OCSP). OCSP allows querying the CA's responder for the status of a specific certificate in real-time.

Answer

Certificate Revocation List (CRL)

Answer

Self-signed certificate validation

Answer

Certificate Transparency (CT)

Question 13

A security team is evaluating hashing algorithms for use in a new system. Which of the following are considered currently secure for general use? (Select TWO)

Accepted Answer

SHA-3. SHA-3 (C) is the latest member of the Secure Hash Algorithm family, standardized by NIST in FIPS 202. It is based on the Keccak sponge construction and is not susceptible to the collision attacks that weaken SHA-1 or the length-extension vulnerabilities of SHA-2, making it currently secure for general use.

Answer

SHA-1

Answer

MD5

Answer

HMAC-SHA256

Question 14

An organization is designing a secure email system using S/MIME. Which of the following are essential components of the PKI that must be in place? (Select THREE)

Accepted Answer

X.509 digital certificates for each user. S/MIME relies on a PKI where each user possesses an X.509 digital certificate that binds their identity to a public key. This certificate is essential for signing and encrypting emails, as it allows recipients to verify the sender's identity and encrypt messages using the sender's public key.

Answer

A symmetric key distribution center (KDC)

Answer

A timestamp authority (TSA)

Question 15

A company is migrating from 3DES to a modern encryption algorithm. Which of the following are acceptable choices? (Select TWO)

Accepted Answer

ChaCha20. AES and ChaCha20 are modern symmetric ciphers considered secure. RC4 is broken, Blowfish is older (64-bit block), and DES is obsolete.

Answer

DES

Answer

RC4

Answer

Blowfish

Question 16

An organization is migrating from 3DES to AES-256 for encrypting data at rest. Which mode of AES is recommended for authenticated encryption?

Accepted Answer

GCM. GCM (Galois/Counter Mode) is the correct choice because it provides both confidentiality and authenticity in a single, efficient mode. For data at rest, authenticated encryption ensures that encrypted data cannot be tampered with undetected, which is critical for integrity. AES-256-GCM is widely recommended and standardized (NIST SP 800-38D) for this purpose.

Answer

ECB

Answer

CBC

Answer

CTR

Question 17

A security analyst is reviewing a digital signature implementation. The signer uses their private key to encrypt the hash of a message. What does the recipient use to verify the signature?

Accepted Answer

The signer's public key. Digital signatures use asymmetric cryptography where the signer encrypts the message hash with their private key. The recipient decrypts that encrypted hash using the signer's public key, then compares it to a locally computed hash of the received message. If they match, the signature is verified, proving both authenticity and integrity.

Answer

The recipient's private key

Answer

The signer's private key

Answer

The recipient's public key

Question 18

Which of the following is a secure hash algorithm currently recommended by NIST?

Accepted Answer

SHA-256. SHA-256 is a member of the SHA-2 family of secure hash algorithms and is currently recommended by NIST for cryptographic use. It produces a 256-bit (32-byte) hash value and is widely deployed in protocols such as TLS, SSH, and IPsec, as well as in digital signatures and certificate validation.

Answer

SHA-1

Answer

RC4

Answer

MD5

Question 19

An organization is configuring a VPN using IPsec. To ensure forward secrecy, which key exchange method should be used?

Accepted Answer

Ephemeral Diffie-Hellman (DHE or ECDHE). Ephemeral Diffie-Hellman (DHE or ECDHE) provides forward secrecy because it generates a temporary, one-time key pair for each session. If the long-term private key is compromised, past session keys cannot be derived, as the ephemeral keys are discarded after use. This ensures that even if an attacker records encrypted traffic and later obtains the private key, they cannot decrypt past sessions.

Answer

RSA key exchange

Answer

Pre-shared key (PSK)

Answer

Static Diffie-Hellman

Question 20

A company is implementing a PKI for internal use. What is the primary purpose of a Certificate Revocation List (CRL)?

Accepted Answer

To publish revoked certificates. The primary purpose of a Certificate Revocation List (CRL) is to publish a list of certificates that have been revoked by the Certificate Authority (CA) before their scheduled expiration. This allows relying parties to verify that a certificate is still valid and has not been compromised, ensuring trust in the PKI.

Answer

To validate certificate chains

Answer

To encrypt certificate requests

Answer

To store all issued certificates

SSCP Cryptography — All Questions With Answers

A security analyst is recommending a symmetric encryption algorithm for a new application that requires both confidentiality and authentication. Which algorithm and mode combination should they select?

An organization is implementing a digital signature solution to ensure non-repudiation of documents. Which combination of keys is used during the signing process?

A company is deploying a VPN using IPsec. They want to ensure that even if the private key of the server is compromised, past session keys cannot be derived. Which key exchange method should they use?

A security administrator is configuring a web server to use TLS. They want to optimize performance while maintaining strong security. Which cipher suite should they prioritize?

Which of the following hash algorithms is considered cryptographically broken and should be avoided due to collision attacks?

An organization uses a PKI with a root CA that issues certificates to intermediate CAs, which then issue end-entity certificates. A client receives an end-entity certificate signed by an intermediate CA. During validation, which certificates are required to build the chain of trust?

A security engineer needs to choose an asymmetric algorithm for a system with limited computational resources, such as an IoT device. The algorithm must provide equivalent security to RSA 2048-bit while using smaller key sizes. Which algorithm should they choose?

A security auditor reviews a system that uses HMAC-SHA256 for message authentication. Which property does HMAC provide that a simple hash of the message does not?

Which of the following is a secure protocol for remote administration of a server, replacing insecure protocols like Telnet?

A company wants to implement a key management system. They need to generate cryptographic keys that are unpredictable. Which source of randomness should be used?

A certificate authority (CA) issues a certificate with the extended key usage (EKU) extension specifying 'serverAuth'. Which of the following is this certificate allowed to do?

Which of the following is a method to check the revocation status of a digital certificate in real-time without the client downloading a full list?

A security team is evaluating hashing algorithms for use in a new system. Which of the following are considered currently secure for general use? (Select TWO)

An organization is designing a secure email system using S/MIME. Which of the following are essential components of the PKI that must be in place? (Select THREE)

A company is migrating from 3DES to a modern encryption algorithm. Which of the following are acceptable choices? (Select TWO)

An organization is migrating from 3DES to AES-256 for encrypting data at rest. Which mode of AES is recommended for authenticated encryption?

A security analyst is reviewing a digital signature implementation. The signer uses their private key to encrypt the hash of a message. What does the recipient use to verify the signature?

Which of the following is a secure hash algorithm currently recommended by NIST?

An organization is configuring a VPN using IPsec. To ensure forward secrecy, which key exchange method should be used?

A company is implementing a PKI for internal use. What is the primary purpose of a Certificate Revocation List (CRL)?

An analyst is comparing symmetric and asymmetric encryption. Which statement accurately describes a typical use case?

Which of the following is a secure alternative to RC4 for stream ciphers?

A security engineer is designing a system that requires non-repudiation of data origin. Which cryptographic technique should be used?

Which of the following best describes the purpose of a Hardware Security Module (HSM) in key management?

An organization is planning to implement ECC for digital signatures. Which key size provides a security level equivalent to a 3072-bit RSA key?

Which protocol is used to provide secure remote shell access and replace Telnet?

In a PKI, what is the role of the root Certificate Authority (CA)?

A security administrator is evaluating encryption protocols for email communication. Which of the following protocols can secure email in transit? (Select TWO)

Which of the following are considered secure cryptographic practices for key management? (Select THREE)

An organization wants to implement a hashing algorithm for integrity checks. Which of the following should be avoided due to known vulnerabilities? (Select TWO)

Which of the following encryption algorithms is classified as a symmetric block cipher and is the current standard recommended by NIST, supporting key sizes of 128, 192, and 256 bits?

A security analyst is evaluating encryption modes for a new system that requires authenticated encryption to ensure both confidentiality and integrity of data in transit. Which AES mode should the analyst recommend?

An organization is moving away from legacy encryption and wants to avoid stream ciphers due to known vulnerabilities. Which of the following algorithms should be avoided because it is a stream cipher with known weaknesses like the BEAST attack?

A security engineer is implementing a digital signature scheme to ensure non-repudiation. Which process correctly describes how a digital signature is created and verified?

Which of the following is a cryptographic hash function that is considered cryptographically broken due to collision attacks and should not be used for security purposes?

An organization wants to implement a key exchange mechanism that provides forward secrecy. Which of the following should be used?

A PKI administrator needs to check the revocation status of a digital certificate without requiring the client to download the entire CRL. Which method is designed for online, real-time certificate status checking?

What is the minimum recommended RSA key size for secure use as of current best practices?

Which of the following protocols is used to securely transfer files over SSH and is considered a replacement for FTP?

In X.509 certificate format, which field is used to specify the fully qualified domain name(s) for which the certificate is valid?

A security professional is designing a key management system and needs to ensure that keys are generated using a truly random source. Which of the following is the most appropriate method for generating cryptographic keys?

Which of the following best describes the difference between HMAC and a simple hash function like SHA-256 when used for message authentication?

A security team is implementing a PKI for a large enterprise. Which TWO of the following are commonly used methods for certificate revocation checking? (Select TWO.)

A company is selecting a cryptographic algorithm for digital signatures. Which THREE of the following algorithms can be used for digital signatures? (Select THREE.)

Which TWO of the following are considered secure cryptographic hash functions as of current standards? (Select TWO.)

A security analyst is evaluating the cryptographic settings for a new application that requires both confidentiality and integrity for data in transit. The analyst needs to choose a symmetric cipher that provides authenticated encryption. Which of the following is the best choice?

A security engineer is designing a key management system for a large enterprise. Which two of the following practices are essential for securing cryptographic keys throughout their lifecycle?

An organization is implementing a digital signature solution to ensure non-repudiation and integrity of documents. Which three of the following are true regarding digital signatures?

A company is upgrading its legacy systems to use modern cryptographic standards. Which two of the following algorithms should be avoided due to known weaknesses or deprecation?

A security administrator is setting up a public key infrastructure (PKI) for internal use. Which two of the following components are essential for establishing a chain of trust from the root CA to end-entity certificates?

SSCP Cryptography — All Questions With Answers

A security analyst is recommending a symmetric encryption algorithm for a new application that requires both confidentiality and authentication. Which algorithm and mode combination should they select?

An organization is implementing a digital signature solution to ensure non-repudiation of documents. Which combination of keys is used during the signing process?

A company is deploying a VPN using IPsec. They want to ensure that even if the private key of the server is compromised, past session keys cannot be derived. Which key exchange method should they use?

A security administrator is configuring a web server to use TLS. They want to optimize performance while maintaining strong security. Which cipher suite should they prioritize?

Which of the following hash algorithms is considered cryptographically broken and should be avoided due to collision attacks?

An organization uses a PKI with a root CA that issues certificates to intermediate CAs, which then issue end-entity certificates. A client receives an end-entity certificate signed by an intermediate CA. During validation, which certificates are required to build the chain of trust?

A security engineer needs to choose an asymmetric algorithm for a system with limited computational resources, such as an IoT device. The algorithm must provide equivalent security to RSA 2048-bit while using smaller key sizes. Which algorithm should they choose?

A security auditor reviews a system that uses HMAC-SHA256 for message authentication. Which property does HMAC provide that a simple hash of the message does not?

Which of the following is a secure protocol for remote administration of a server, replacing insecure protocols like Telnet?

A company wants to implement a key management system. They need to generate cryptographic keys that are unpredictable. Which source of randomness should be used?

A certificate authority (CA) issues a certificate with the extended key usage (EKU) extension specifying 'serverAuth'. Which of the following is this certificate allowed to do?

Which of the following is a method to check the revocation status of a digital certificate in real-time without the client downloading a full list?

A security team is evaluating hashing algorithms for use in a new system. Which of the following are considered currently secure for general use? (Select TWO)

An organization is designing a secure email system using S/MIME. Which of the following are essential components of the PKI that must be in place? (Select THREE)

A company is migrating from 3DES to a modern encryption algorithm. Which of the following are acceptable choices? (Select TWO)

An organization is migrating from 3DES to AES-256 for encrypting data at rest. Which mode of AES is recommended for authenticated encryption?

A security analyst is reviewing a digital signature implementation. The signer uses their private key to encrypt the hash of a message. What does the recipient use to verify the signature?

Which of the following is a secure hash algorithm currently recommended by NIST?

An organization is configuring a VPN using IPsec. To ensure forward secrecy, which key exchange method should be used?

A company is implementing a PKI for internal use. What is the primary purpose of a Certificate Revocation List (CRL)?

An analyst is comparing symmetric and asymmetric encryption. Which statement accurately describes a typical use case?

Which of the following is a secure alternative to RC4 for stream ciphers?

A security engineer is designing a system that requires non-repudiation of data origin. Which cryptographic technique should be used?

Which of the following best describes the purpose of a Hardware Security Module (HSM) in key management?

An organization is planning to implement ECC for digital signatures. Which key size provides a security level equivalent to a 3072-bit RSA key?

Which protocol is used to provide secure remote shell access and replace Telnet?

In a PKI, what is the role of the root Certificate Authority (CA)?

A security administrator is evaluating encryption protocols for email communication. Which of the following protocols can secure email in transit? (Select TWO)