ThreatFox: AdaptixC2 IOCs

Hunt Hypothesis

This hunt detects adversary activity involving the AdaptixC2 command and control infrastructure by identifying matches against three specific Indicators of Compromise (IOCs). Proactive hunting for these signals in Azure Sentinel is critical to rapidly uncover early-stage lateral movement or data exfiltration attempts that may evade standard signature-based detections.

IOC Summary

Malware Family: AdaptixC2 Total IOCs: 3 IOC Types: ip:port

KQL: Ip Hunt

// Hunt for network connections to known malicious IPs
// Source: ThreatFox - AdaptixC2
let malicious_ips = dynamic(["4.228.96.20", "45.195.8.67"]);
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(["4.228.96.20", "45.195.8.67"]);
DeviceNetworkEvents
| where RemoteIP in (malicious_ips)
| project Timestamp, DeviceName, RemoteIP, RemotePort, InitiatingProcessFileName, ActionType
| order by Timestamp desc

Required Data Sources

References

• ThreatFox — AdaptixC2

False Positive Guidance

Here are specific false positive scenarios and corresponding exclusion strategies for the ThreatFox: AdaptixC2 IOCs detection rule in an enterprise environment:

• Scenario: Endpoint Protection Software Updates

  • Context: Enterprise EDR agents (e.g., CrowdStrike Falcon, Microsoft Defender for Endpoint) frequently download definition updates or configuration profiles from cloud repositories that may share IP addresses or domain hashes with the AdaptixC2 IOCs. This often occurs during scheduled nightly maintenance windows.
  • Suggested Filter/Exclusion: Create a process-based exclusion to ignore alerts where the parent process is the EDR service (e.g., FalconSensor.exe or MsMpEng.exe) and the network destination matches known update server ranges defined in the threat intelligence feed.

• Scenario: Scheduled Backup Jobs

  • Context: Automated backup solutions like Veeam Backup & Replication or Rubrik often initiate connections to cloud storage gateways or management consoles that utilize infrastructure overlapping with AdaptixC2 indicators. These jobs typically run on a cron schedule (e.g., every Sunday at 02:00) and generate high-volume network traffic.
  • Suggested Filter/Exclusion: Implement a time-based exclusion window for the rule during known backup maintenance hours, or add specific source IP ranges of the internal backup servers to an allow-list if they consistently trigger the IOCs without malicious behavior.

• Scenario: Third-Party Cloud Management Tools

  • Context: Administrative tasks involving cloud management platforms (e.g., AWS Systems Manager, Azure Monitor agents) may communicate with external SaaS endpoints that match the AdaptixC2 domain signatures. This is common when IT admins trigger manual health checks or inventory scans via these tools.
  • Suggested Filter/Exclusion: Exclude alerts where the initiating user account belongs to a specific “Service Account” group (