Packet sniffing is a type of network attack that can directly affect the confidentiality of an unencrypted VoIP network. In packet sniffing, an attacker captures data packets as they travel across the network. Since VoIP calls transmit voice data in the form of data packets, an unencrypted VoIP network is particularly vulnerable to this type of attack. The attacker can potentially listen to the conversations or extract sensitive information from these packets. This compromises the confidentiality principle of information security, which aims to protect information from unauthorized disclosure12.

Brute Force Attack (B) and Ransomware © are more related to the integrity and availability of systems rather than confidentiality. Vishing Attack (D) is a form of phishing which involves social engineering over telephone systems but does not directly affect the network’s confidentiality like packet sniffing does.

References :=

Information Security Management Principles, 3rd Edition1.

VoIP Hacking: How It Works & How to Protect Your VoIP Phone3.