Performing Network Traffic Analysis with TShark

Overview

This skill automates packet capture analysis using tshark (Wireshark CLI) and pyshark (Python wrapper). It extracts protocol distribution statistics, identifies suspicious network flows (port scans, beaconing, data exfiltration), extracts IOCs (IPs, domains, URLs), and detects DNS tunneling patterns from PCAP files.

Prerequisites

• tshark (Wireshark CLI) installed and in PATH
• Python 3.8+ with pyshark library
• PCAP or PCAPNG capture file for analysis

Steps

1. Extract Protocol Statistics — Generate protocol hierarchy and conversation statistics from the capture
2. Identify Top Talkers — Rank source/destination IPs by volume and connection count
3. Detect Suspicious Flows — Flag port scanning patterns, unusual port usage, and high-frequency connections
4. Extract Network IOCs — Pull unique IPs, domains from DNS queries, and URLs from HTTP traffic
5. Analyze DNS Traffic — Detect DNS tunneling via high-entropy subdomain queries and excessive TXT records
6. Generate Analysis Report — Produce structured report with flow summaries and threat indicators

Expected Output

• JSON report with protocol statistics and top talkers
• Suspicious flow detections with severity ratings
• Extracted IOCs (IPs, domains, URLs)
• DNS anomaly analysis results

Verification Criteria

Confirm successful execution by validating:

• [ ] All prerequisite tools and access requirements are satisfied
• [ ] Each workflow step completed without errors
• [ ] Output matches expected format and contains expected data
• [ ] No security warnings or misconfigurations detected
• [ ] Results are documented and evidence is preserved for audit

Compliance Framework Mapping

This skill supports compliance evidence collection across multiple frameworks:

• SOC 2: CC6.6 (System Boundaries), CC6.7 (Restriction on Transmission)
• ISO 27001: A.13.1 (Network Security), A.13.2 (Information Transfer)
• NIST 800-53: SC-7 (Boundary Protection), AC-17 (Remote Access), SI-4 (System Monitoring)
• NIST CSF: PR.AC (Access Control), PR.PT (Protective Technology)

Claw GRC Tip: When this skill is executed by a registered agent, compliance evidence is automatically captured and mapped to the relevant controls in your active frameworks.

Deploying This Skill with Claw GRC

Agent Execution

Register this skill with your Claw GRC agent for automated execution:

# Install via CLI
npx claw-grc skills add performing-network-traffic-analysis-with-tshark

# Or load dynamically via MCP
grc.load_skill("performing-network-traffic-analysis-with-tshark")

Audit Trail Integration

When executed through Claw GRC, every step of this skill generates tamper-evident audit records:

• SHA-256 chain hashing ensures no step can be modified after execution
• Evidence artifacts (configs, scan results, logs) are automatically attached to relevant controls
• Trust score impact — successful execution increases your agent's trust score

Continuous Compliance

Schedule this skill for recurring execution to maintain continuous compliance posture. Claw GRC monitors for drift and alerts when re-execution is needed.