Files
Anthropic-Cybersecurity-Skills/skills/analyzing-network-flow-data-with-netflow/SKILL.md
T
mukul975 c47eed6a64 Production hardening: security fixes, code quality, 724 skills complete
- Fix 25 shell=True subprocess calls with list-based commands
- Fix 49 verify=False in defensive skills (env-var override)
- Add timeout to 231 HTTP/subprocess/socket calls
- Fix 6 SQL injection patterns with whitelist validation
- Replace 8 __import__() with standard imports
- Remove 701 unused imports across 442 files
- Add authorized-testing disclaimers to all offensive skills
- Complete 11 incomplete skill directories
- Expand 10 stub SKILL.md files with full content
- Fix 2 YAML parse errors in frontmatter
- Fix 5 pre-existing syntax errors
- Convert 22 hardcoded paths/ports to environment variables
- Back up 21 redundant skill pairs to .bak
- Fix 2 global declaration errors
- 724/724 skills with full folder anatomy (SKILL.md + agent.py + api-reference.md + LICENSE)
- 0 compile errors across all 724 agent.py files
2026-03-19 13:26:49 +01:00

1.5 KiB

name, description, domain, subdomain, tags, version, author, license
name description domain subdomain tags version author license
analyzing-network-flow-data-with-netflow Parse NetFlow v9 and IPFIX records to detect volumetric anomalies, port scanning, data exfiltration, and C2 beaconing patterns. Uses the Python netflow library to decode flow records, builds traffic baselines, and applies statistical analysis to identify flows with abnormal byte counts, connection durations, and periodic timing patterns. cybersecurity network-security
analyzing
network
flow
data
1.0 mahipal Apache-2.0

Analyzing Network Flow Data with Netflow

Instructions

  1. Install dependencies: pip install netflow
  2. Collect NetFlow/IPFIX data from routers or use the built-in collector: python -m netflow.collector -p 9995
  3. Parse captured flow data using netflow.parse_packet().
  4. Analyze flows for:
    • Port scanning: single source to many destinations on same port
    • Data exfiltration: high byte-count outbound flows to unusual destinations
    • C2 beaconing: periodic connections with consistent intervals
    • Volumetric anomalies: traffic spikes beyond baseline thresholds
  5. Generate a prioritized findings report.
python scripts/agent.py --flow-file captured_flows.json --output netflow_report.json

Examples

Parse NetFlow v9 Packet

import netflow
data, _ = netflow.parse_packet(raw_bytes, templates={})
for flow in data.flows:
    print(flow.IPV4_SRC_ADDR, flow.IPV4_DST_ADDR, flow.IN_BYTES)