This attack is a form of vishing, which is a portmanteau of "voice" and "phishing." Vishing attacks use voice communication technology, such as a phone call or voicemail, to conduct phishing. In this scenario, the attacker leaves a fraudulent voicemail, impersonating a legitimate company to deceive the recipient into revealing sensitive financial information (a credit card number). The use of a voice message as the attack vector is the defining characteristic of vishing, making it the most accurate and specific answer.

A. Phishing: This is a general term for attacks seeking sensitive information via electronic communication. Vishing is a more specific and accurate description of this voice-based attack.

B. Spear phishing: This describes a targeted attack, which this is, as it references a recent purchase. However, "vishing" is more precise as it specifically identifies the voice-based medium used.

C. Whaling: This is a type of spear phishing that specifically targets high-profile individuals like executives or celebrities. The scenario does not indicate the victim is a high-value target.

1. National Institute of Standards and Technology (NIST). Glossary of Key Information Security Terms

NISTIR 7298 Rev. 3. Page 207. "Vishing: A type of phishing attack that is conducted over the phone

using voice technology (e.g.

a phone call or voice message)."

This source also defines spear phishing (p. 178) as a targeted attack and whaling (p. 210) as targeting high-profile individuals

supporting the distinctions made above.

2. Purdue University. Information Security and Policy

Social Engineering. "Vishing is another type of phishing attack that is conducted by phone... Spear phishing is a more targeted phishing attack. The attacker finds out information about the target..."

This university resource clearly distinguishes the terms

defining vishing by its voice medium and spear phishing by its targeted nature. The scenario's most explicit detail is the voice message

making vishing the most precise classification.

3. Carnegie Mellon University

Software Engineering Institute (SEI). Common Social Engineering Attacks. "Vishing

or voice phishing

is the use of telephony... to trick individuals into revealing sensitive information."

This further solidifies the definition of vishing as an attack conducted over voice channels

directly matching the scenario described.