A security analyst discovers that an attacker has been intercepting and relaying messages between two users without their knowledge. The attacker can read and modify the messages, but the users believe they are communicating directly. Which cryptographic property has been violated?

Confidentiality, integrity, and authentication.

A security analyst is investigating a phishing attack where users were tricked into visiting a fraudulent website. The website presented a valid TLS certificate issued by a legitimate public CA, but the domain name did not match the organization's real domain. Which PKI weakness or misconfiguration allowed this attack to succeed?

The browser failed to check the certificate revocation list (CRL).

The CA's root certificate was compromised, allowing the attacker to issue any certificate.

The certificate was self-signed and the user clicked through the warning.

The CA issued a certificate for a domain that the attacker controlled, and the browser did not detect the domain mismatch because the user ignored the warning.

A legal team needs to prove that a specific employee signed a contract electronically. The employee used a private key to sign the document. What property does this provide?

Integrity, but not authentication.

Confidentiality, because the document is encrypted.

Availability, because the signature ensures the document is accessible.

Non-repudiation, because only the holder of the private key could have created the signature.

A security team is evaluating whether to use MD5 or SHA-256 for hashing passwords in a legacy system. The system currently stores MD5 hashes, but the team is concerned about collision attacks. What is the BEST course of action?

Use MD5 with a salt to prevent collisions.

Continue using MD5 because it is faster and the system is legacy.

Migrate to SHA-256 and rehash all existing passwords.

Use SHA-256 for new passwords but leave existing MD5 hashes unchanged.

In a typical secure communication session, why is symmetric encryption often used for the bulk data after an initial asymmetric key exchange?

Symmetric encryption eliminates the need for key distribution.

Symmetric encryption is the only type that can encrypt streaming data.

Symmetric encryption provides stronger authentication than asymmetric.

Symmetric encryption is faster and more efficient for large amounts of data.

GIAC Information Security Fundamentals

Domain 4Objective 1

Foundations of Cryptography and Digital Trust GISF Practice Questions (Page 7)

Part of the Cryptography and Identity domain, which makes up ~14% of our current practice bank. GIAC (SANS) does not publish an official question count, but from its 120-minute exam (~50–80 total, ~7–11 in this domain), expect 4–6 from this objective — we provide 45 practice questions to prepare you well beyond it. (estimate)

45questions here

9free pages

7concepts

Questions 31–35

31expert · hard
A security analyst discovers that an attacker has been intercepting and relaying messages between two users without their knowledge. The attacker can read and modify the messages, but the users believe they are communicating directly. Which cryptographic property has been violated?
Select an answer first
32expert · hard
A security analyst is investigating a phishing attack where users were tricked into visiting a fraudulent website. The website presented a valid TLS certificate issued by a legitimate public CA, but the domain name did not match the organization's real domain. Which PKI weakness or misconfiguration allowed this attack to succeed?
Select an answer first
33application · medium
A legal team needs to prove that a specific employee signed a contract electronically. The employee used a private key to sign the document. What property does this provide?
Select an answer first
34expert · hard
A security team is evaluating whether to use MD5 or SHA-256 for hashing passwords in a legacy system. The system currently stores MD5 hashes, but the team is concerned about collision attacks. What is the BEST course of action?
Select an answer first
35foundation · easy
In a typical secure communication session, why is symmetric encryption often used for the bulk data after an initial asymmetric key exchange?
Select an answer first

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