Definition:
Packet sniffing is the process of intercepting and logging network traffic as it passes over a digital network.

Purpose:
Used for network diagnostics, but also exploited by attackers to capture sensitive data like passwords, emails, and files.

How it works:

  • The sniffer listens to packets using promiscuous mode on a network interface.

  • It can capture unencrypted data.

Tools: Wireshark, tcpdump, Ettercap

Risks:

  • Data theft on unsecured networks (e.g., open Wi-Fi).

  • Violation of privacy.

Prevention:

  • Use encryption (HTTPS, VPN).

  • Switch to switched networks instead of hubs.

  • Monitor for unusual sniffing activity.