Anthropic-Cybersecurity-Skills/skills/analyzing-network-traffic-for-incidents/references/api-reference.md

API Reference: Network Traffic Incident Analysis

tshark - CLI Wireshark

Basic Syntax

tshark -r <pcap_file> [options]

Display Filters

tshark -r capture.pcap -Y "ip.addr==10.0.0.5"
tshark -r capture.pcap -Y "tcp.port==445"         # SMB
tshark -r capture.pcap -Y "http.request"           # HTTP requests
tshark -r capture.pcap -Y "dns.qr==0"              # DNS queries
tshark -r capture.pcap -Y "tcp.flags.syn==1 && tcp.flags.ack==0"  # SYN only

Field Extraction

tshark -r capture.pcap -T fields -e ip.src -e ip.dst -e tcp.dstport \
  -Y "tcp.flags.syn==1"

Statistics

tshark -r capture.pcap -q -z conv,ip       # IP conversations
tshark -r capture.pcap -q -z endpoints,ip  # IP endpoints
tshark -r capture.pcap -q -z io,stat,60    # I/O stats per minute
tshark -r capture.pcap -q -z http,tree     # HTTP request tree
tshark -r capture.pcap -q -z dns,tree      # DNS query tree

Object Export

tshark -r capture.pcap --export-objects "http,/tmp/http_objects"
tshark -r capture.pcap --export-objects "smb,/tmp/smb_objects"

Zeek - Network Security Monitor

PCAP Analysis

zeek -r capture.pcap
zeek -r capture.pcap local     # With local policy scripts

Output Logs

Log File	Content
conn.log	TCP/UDP/ICMP connections
dns.log	DNS queries and responses
http.log	HTTP requests
ssl.log	TLS/SSL handshakes
files.log	File transfers
notice.log	Security notices

Zeek-Cut Field Extraction

cat conn.log | zeek-cut id.orig_h id.resp_h id.resp_p proto service
cat dns.log | zeek-cut query qtype_name answers
cat http.log | zeek-cut host uri method user_agent

Suricata - IDS/IPS

PCAP Analysis

suricata -r capture.pcap -l /tmp/output -k none
suricata -r capture.pcap -S custom.rules -l /tmp/output

Output Files

File	Content
fast.log	One-line alert format
eve.json	JSON event log (detailed)
stats.log	Engine performance statistics

Lateral Movement Ports

Port	Service	Significance
445	SMB	File shares, PsExec, WMI
3389	RDP	Remote Desktop
5985/5986	WinRM	PowerShell Remoting
22	SSH	Secure Shell
135	RPC	DCOM, WMI
139	NetBIOS	Legacy file sharing

Scapy - Packet Analysis (Python)

PCAP Reading

from scapy.all import rdpcap, IP, TCP
packets = rdpcap("capture.pcap")
for pkt in packets:
    if IP in pkt and TCP in pkt:
        print(pkt[IP].src, pkt[TCP].dport)

NetworkMiner - Artifact Extraction

Syntax

NetworkMiner --inputfile capture.pcap --outputdir /tmp/artifacts

Extracts: files, images, credentials, sessions, DNS, parameters