ThreatFox: AsyncRAT IOCs

Hunt Hypothesis

This hunt detects adversary activity involving four specific indicators of compromise (IOCs) linked to the AsyncRAT remote access trojan, which is frequently used by threat actors for command and control operations within Azure Sentinel environments. Proactive hunting for these IOCs is critical because AsyncRAT enables persistent lateral movement and data exfiltration capabilities that often evade standard signature-based detections until significant impact occurs.

IOC Summary

Malware Family: AsyncRAT Total IOCs: 4 IOC Types: ip:port

Type	Value	Threat Type	First Seen	Confidence
ip:port	`195[.]177[.]94[.]169:8080`	botnet_cc	2026-07-31	75%
ip:port	`194[.]59[.]30[.]109:6606`	botnet_cc	2026-07-31	75%
ip:port	`157[.]254[.]194[.]126:1447`	botnet_cc	2026-07-31	75%
ip:port	`104[.]243[.]248[.]63:3608`	botnet_cc	2026-07-31	75%

KQL: Ip Hunt

// Hunt for network connections to known malicious IPs
// Source: ThreatFox - AsyncRAT
let malicious_ips = dynamic(["104.243.248.63", "195.177.94.169", "194.59.30.109", "157.254.194.126"]);
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(["104.243.248.63", "195.177.94.169", "194.59.30.109", "157.254.194.126"]);
DeviceNetworkEvents
| where RemoteIP in (malicious_ips)
| project Timestamp, DeviceName, RemoteIP, RemotePort, InitiatingProcessFileName, ActionType
| order by Timestamp desc

Required Data Sources

Sentinel Table	Notes
`CommonSecurityLog`	Ensure this data connector is enabled
`DeviceNetworkEvents`	Ensure this data connector is enabled

References

ThreatFox — AsyncRAT

False Positive Guidance

Here are specific false positive scenarios for the ThreatFox: AsyncRAT IOCs detection rule, including suggested filters and exclusions tailored for an enterprise environment:

Scenario: Legitimate Remote Administration via TeamViewer or AnyDesk
- Context: Enterprise IT support teams frequently use remote desktop tools like TeamViewer, AnyDesk, or Splashtop to troubleshoot endpoints. These applications often establish outbound connections to their respective update and control servers (e.g., teamviewer.com, anydesk.com) using ports and TLS patterns that closely mimic AsyncRAT’s C2 behavior, triggering the “Outbound Connection” IOC.
- Suggested Filter/Exclusion: Create a whitelist exclusion for known benign remote administration domains. Specifically, exclude traffic where the destination domain matches *.teamviewer.com, *.anydesk.com, or *.splashtop.com and the process name is TeamViewer.exe or AnyDesk.exe.
Scenario: Scheduled Software Update Jobs (e.g., Microsoft Update or SCCM)
- Context: Automated patch management systems like Microsoft Endpoint Configuration Manager (SCCM/MECM) or WSUS run scheduled jobs during business hours to download and install updates. These processes often initiate network connections to update servers that match the AsyncRAT “File Download” or “Heartbeat” IOCs, particularly when downloading large payloads over HTTPS.
- Suggested Filter/Exclusion: Implement a process-based exclusion for wuauclt.exe, usoclient.exe, and ccmexec.exe. Additionally, add a time-window filter to suppress alerts generated by these processes between 02:00 and 06:00 local time, coinciding with standard maintenance windows.
Scenario: Internal DevOps CI/CD Pipeline Artifacts *