analyzing-network-traffic-of-malware

# Analyzing Network Traffic of Malware ## When to Use - Sandbox execution has captured a PCAP file and the network behavior needs detailed analysis - Identifying the C2 protocol structure for writing network detection signatures - Determining what data the malware exfiltrates and to which external infrastructure - Analyzing DNS tunneling, domain generation algorithms (DGA), or fast-flux behavior - Creating Suricata/Snort signatures based on observed malware network patterns **Do not use** for host-based analysis of malware behavior; use Cuckoo sandbox reports or Volatility memory analysis for process-level activity. ## Prerequisites - Wireshark 4.x installed for interactive PCAP analysis - tshark (Wireshark CLI) for scripted packet extraction - Zeek installed for automated metadata generation from PCAPs - Suricata with ET Open/ET Pro rulesets for signature matching - NetworkMiner for file extraction and credential detection from PCAPs - Python 3.8+ with `scapy` and `dpkt` for programmatic packet analysis ## Workflow ### Step 1: Initial PCAP Overview Get a high-level understanding of the network traffic: ```bash # Capture statistics capinfos malware.pcap # Protocol hierarchy tshark -r malware.pcap -q -z io,phs # Endpoint statistics (top talkers) tshark -r malware.pcap -q -z endpoints,ip # Conversation statistics tshark -r malware.pcap -q -z conv,tcp # DNS query summary tshark -r malware.pcap -q -z dns,tree ``` ### Step 2: Analyze DNS Activity Examine DNS queries...