Wireshark is a network packet analyzer used to capture and analyze network traffic in real-time. During a penetration test, it is often used to inspect unencrypted communication to extract sensitive information like plaintext login credentials. Here's how it works:

Packet Capturing:Wireshark captures the network packets transmitted over a network interface. If a user logs in through an insecure communication protocol (e.g., HTTP, FTP, or Telnet), the credentials are transmitted in plaintext.

Traffic Filtering:Using filters (e.g., http, tcp.port == 21), the tester narrows down the relevant traffic to locate the login request and response packets.

Sensitive Data Extraction:Analyzing the captured packets reveals plaintext credentials in the data payload, such as in HTTP POST requests.

Exploit the Information:After extracting the plaintext credentials, the tester can attempt unauthorized access to resources using these credentials.

CompTIA Pentest+ References:

Domain 1.0 (Planning and Scoping)

Domain 2.0 (Information Gathering and Vulnerability Identification)

Wireshark Usage Guide