What is Whois Footprinting?

What is Network Sniffing?

Network sniffing involves monitoring data transmitted over a network to analyze traffic patterns, identify vulnerabilities, and detect security threats. It plays a key role in network diagnostics, penetration testing, and cybersecurity investigations. Sniffing can be categorized into two types: passive sniffing, which captures data without modification, usually on non-switch networks, and active sniffing, which manipulates the network to capture data on switch-based networks by intercepting or redirecting traffic. Attackers achieve this by using techniques such as ARP spoofing, MAC flooding, or DHCP attacks to redirect or mirror traffic to their devices.

 

Network Sniffing Techniques

1. Packet Capture and Analysis

Captures raw packets for analysis using tools like Wireshark and tcpdump, identifying insecure communications or unusual behavior in network traffic, helping reveal vulnerabilities and unauthorized data flows.

2. ARP Spoofing (ARP Poisoning)

Uses fake ARP messages to redirect traffic through the attacker’s device, enabling interception of sensitive data, such as credentials, and creating Man-in-the-Middle (MITM) attack scenarios on unsecured networks.

3. DNS Spoofing

Redirects legitimate DNS requests to malicious sites by altering DNS responses, allowing attackers to capture login credentials or inject malware, often used in controlled tests for phishing awareness training.

4.MAC Flooding

Overloads a switch’s MAC table, forcing it into hub mode, which enables sniffing of all network traffic. This technique helps access packets otherwise restricted on a switched network.

5. DHCP Spoofing

Acts as a rogue DHCP server, assigning malicious IP and gateway configurations to redirect network traffic through the attacker’s device, enabling interception of sensitive data in testing scenarios.

6. Wi-Fi Sniffing

Captures Wi-Fi traffic by setting the adapter to monitor mode, exposing unencrypted data and weak access points. Tools like Aircrack-ng help identify vulnerabilities in wireless network configurations.

7. SSL Stripping

Downgrades HTTPS connections to HTTP, allowing data interception in plaintext. Ethical Hackers use SSLstrip to test HTTPS enforcement and check for proper security headers on web applications.

 

Final Thoughts for Aspiring Ethical Hackers

When practicing network sniffing techniques, keep these best practices in mind:

• Stay Within Legal Boundaries: Ensure you have permission to conduct sniffing on the network you're analyzing.
• Use Labs for Practice: Practice these techniques in virtualized or isolated environments to avoid unintentional disruption.
• Employ Proper Documentation: Always log your activities and findings for accountability.
• Stay Updated on Detection Mechanisms: Many of these techniques have known defense mechanisms, so understanding both attack and defense enhances your skills as a security professional.

 

CEH v13 AI with InfosecTrain

InfosecTrain's Ethical Hacking Training course provides hands-on training in network sniffing, covering key techniques, tools, and ethical guidelines. It equips learners with practical skills to identify vulnerabilities, secure networks, and conduct authorized traffic analysis effectively.