Analyzing Network Packets with Scapy

Overview

Scapy is a Python packet manipulation library that enables crafting, sending, sniffing, and dissecting network packets at granular protocol layers. This skill covers using Scapy for security-relevant tasks including TCP/UDP/ICMP packet crafting, pcap file analysis, protocol field extraction, SYN scan implementation, DNS query analysis, and detecting anomalous traffic patterns such as unusually fragmented packets or malformed headers.

When to Use

• When investigating security incidents that require analyzing network packets with scapy
• When building detection rules or threat hunting queries for this domain
• When SOC analysts need structured procedures for this analysis type
• When validating security monitoring coverage for related attack techniques

Prerequisites

• Python 3.8+ with scapy library installed (pip install scapy)
• Root/administrator privileges for raw socket operations (sniffing, sending)
• Npcap (Windows) or libpcap (Linux) for packet capture