Utilizing ASNs for Hunting & Response

Source: Huntress Blog

Author: unknown

URL: https://www.huntress.com/blog/utilizing-asns-for-hunting-and-response

1. ONE SENTENCE SUMMARY: ASN enrichment of IP addresses significantly enhances threat detection and incident response effectiveness beyond basic geolocation data alone.

2. MAIN POINTS:

3. IP addresses are important but limited without enrichment for investigative analysis.

4. Autonomous Systems Numbers (ASNs) identify networks with unified routing policies.

5. ASN enrichment provides context beyond basic geographic IP address data.

6. Knowing an IP’s ASN can distinguish residential ISPs from suspicious hosting providers.

7. ASN data helped identify compromised accounts during remote desktop intrusions.

8. ASN telemetry highlighted malicious authentications in a RADIUS password spray incident.

9. Geolocation alone failed to detect compromise, underscoring ASN enrichment’s value.

10. VPN compromise cases frequently rely on ASN data to confirm malicious behavior.

11. Authentication anomalies identified via ASN enrichment can guide security responses.

12. ASN enrichment supports accurate narrative building and risk-based security recommendations.

13. TAKEAWAYS:

14. Always enrich IP addresses with ASN data during investigations.

15. Do not rely solely on IP geolocation; ASN adds critical context.

16. Analyze authentication patterns alongside ASN data to detect anomalies.

17. Recognize that certain ASNs frequently correlate with malicious activities.

18. Integrate ASN telemetry systematically into threat hunting workflows.