Sniffing

Sniffing refers to the practice of intercepting and monitoring data packets as they travel across a network. In the CEH (Certified Ethical Hacker) framework, it's considered a passive attack technique where attackers capture network traffic to extract valuable information. Sniffing works by placing a network interface in promiscuous mode, allowing it to capture all packets on the network segment, not just those addressed to it. This can be done using specialized software tools called packet sniffers or network analyzers (such as Wireshark, tcpdump, or Ettercap). Sniffing attacks exploit vulnerabilities in network protocols, particularly those that transmit data in plaintext. The primary targets include: 1. Login credentials: Usernames and passwords sent over unencrypted protocols 2. Email contents transmitted via POP3, IMAP, or SMTP 3. File transfers using FTP 4. Web browsing information over HTTP 5. Telnet sessions Sniffing can be categorized as: - Passive sniffing: Simply listening to network traffic in hub environments or wireless networks - Active sniffing: Using techniques like MAC flooding, ARP poisoning, or DHCP attacks to redirect traffic through the attacker's machine in switched environments Ethical hackers use sniffing to identify security weaknesses, analyze network protocols, troubleshoot network issues, and demonstrate the risks of unencrypted communications. To protect against sniffing attacks, organizations should implement encryption (SSL/TLS, IPsec), use secure protocols (HTTPS, SSH, SFTP), employ switch-based networks, utilize encrypted VPNs, and regularly scan for unauthorized sniffers. Sniffing represents a significant threat in insecure networks, as it allows attackers to collect sensitive information while leaving minimal traces of their activities.

Sniffing refers to the practice of intercepting and monitoring data packets as they travel across a network. In the CEH (Certified Ethical Hacker) framework, it's considered a passive attack techniqu…

Concepts covered: Sniffing Concepts, Sniffing Technique: MAC Attacks, Sniffing Technique: DHCP Attacks, Sniffing Technique: ARP Poisoning, Sniffing Technique: Spoofing Attacks, Sniffing Technique: DNS Poisoning, Sniffing Tools, Sniffing Countermeasures, Sniffing Detection Techniques