ThreatFox: Havoc IOCs

Hunt Hypothesis

This hunt hypothesis targets adversary behavior involving the deployment of Havoc C2 infrastructure by detecting specific Indicators of Compromise (IOCs) linked to its network communications and file artifacts. Proactive hunting for these signatures in Azure Sentinel is critical because Havoc’s modular architecture allows attackers to rapidly establish persistent command-and-control channels that may evade standard signature-based defenses without deep IOC correlation.

IOC Summary

Malware Family: Havoc Total IOCs: 2 IOC Types: ip:port

KQL: Ip Hunt

// Hunt for network connections to known malicious IPs
// Source: ThreatFox - Havoc
let malicious_ips = dynamic(["37.235.54.142", "172.86.119.141"]);
CommonSecurityLog
| where DestinationIP in (malicious_ips) or SourceIP in (malicious_ips)
| project TimeGenerated, SourceIP, DestinationIP, DestinationPort, DeviceAction, Activity
| order by TimeGenerated desc

KQL: Ip Hunt Device

// Hunt in Defender for Endpoint network events
let malicious_ips = dynamic(["37.235.54.142", "172.86.119.141"]);
DeviceNetworkEvents
| where RemoteIP in (malicious_ips)
| project Timestamp, DeviceName, RemoteIP, RemotePort, InitiatingProcessFileName, ActionType
| order by Timestamp desc

Required Data Sources

References

• ThreatFox — Havoc

False Positive Guidance

Here are specific false positive scenarios for the ThreatFox: Havoc IOCs detection rule in an enterprise environment, including targeted filters and exclusions:

• Endpoint Management Agent Updates

  • Scenario: The organization utilizes Microsoft Intune or Jamf Pro to push firmware updates or security patches. These agents often download large payload files from public repositories that share IP addresses or file hashes with known Havoc infrastructure (e.g., a shared CDN node used by both the update service and the threat actor).
  • Filter/Exclusion: Create an exclusion for traffic originating from specific Intune Management Service IPs or destination ports associated with the update agent’s communication channel. Additionally, exclude file hashes that match the known “Good” signature of the latest patch package version (e.g., SHA256: a1b2...c3d4 corresponding to JamfPro-Agent-v4.2.exe).

• Scheduled Backup and Disaster Recovery Jobs

  • Scenario: A nightly scheduled job running on a Windows Server 2022 utilizing Veeam Backup & Replication connects to an external cloud storage provider (e.g., AWS S3 or Azure Blob) for offsite replication. The backup server initiates connections to IP ranges that overlap with Havoc’s command and control infrastructure due to the use of shared public load balancers.
  • Filter/Exclusion: Exclude network flows where the source process is VeeamAgent.exe (or similar service name) running under a dedicated service account (e.g., svc_backup_prod) during defined maintenance windows (e.g., 02:00–06:00 UTC). This can be implemented via a time-based filter on the SIEM ingestion pipeline.

• Third-Party SaaS Integration Probes

  • **Scenario