ThreatFox: DCRat IOCs

Hunt Hypothesis

This detection rule identifies adversary activity involving the DCRat Remote Access Trojan, which grants attackers persistent remote control and command execution capabilities on compromised endpoints. A proactive hunt for these indicators is essential in Azure Sentinel to rapidly uncover stealthy lateral movements and prevent potential data exfiltration or credential theft before adversaries establish a foothold within the network.

IOC Summary

Malware Family: DCRat Total IOCs: 4 IOC Types: ip:port, url

KQL: Ip Hunt

// Hunt for network connections to known malicious IPs
// Source: ThreatFox - DCRat
let malicious_ips = dynamic(["38.60.253.24", "43.248.9.242", "172.86.77.50"]);
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(["38.60.253.24", "43.248.9.242", "172.86.77.50"]);
DeviceNetworkEvents
| where RemoteIP in (malicious_ips)
| project Timestamp, DeviceName, RemoteIP, RemotePort, InitiatingProcessFileName, ActionType
| order by Timestamp desc

KQL: Url Hunt

// Hunt for access to known malicious URLs
// Source: ThreatFox - DCRat
let malicious_urls = dynamic(["http://cq609149.tw1.ru/L1nc0In.php"]);
UrlClickEvents
| where Url has_any (malicious_urls)
| project Timestamp, AccountUpn, Url, ActionType, IsClickedThrough
| order by Timestamp desc

Required Data Sources

References

• ThreatFox — DCRat

False Positive Guidance

Here are 5 specific false positive scenarios for the ThreatFox: DCRat IOCs detection rule, including context and suggested filters:

• Scenario: Legitimate RMM Agent Updates

  • Context: Enterprise Remote Monitoring and Management (RMM) tools like ManageEngine Desktop Central, NinjaOne, or PDQ Deploy often utilize background processes to push patches or execute remote commands. These agents may spawn svchost.exe or specific service executables that match DCRat’s known file hashes or network connection patterns (e.g., connecting to a central management server on non-standard ports).
  • Suggested Filter: Exclude alerts where the parent process is a known RMM agent executable (e.g., NinjaOneAgent.exe, PDQDeployService.exe) and the destination IP belongs to the internal corporate RMM subnet.

• Scenario: Scheduled PowerShell Administrative Jobs

  • Context: System administrators frequently schedule PowerShell scripts via Windows Task Scheduler to perform routine maintenance, such as log rotation, user provisioning, or inventory collection. If these scripts invoke powershell.exe with specific command-line arguments that mimic DCRat’s execution flow (e.g., downloading configuration files from an internal repository), they may trigger the rule.
  • Suggested Filter: Create a whitelist for Task Scheduler jobs named “Daily Admin Maintenance” or similar, specifically filtering out events where the process path is %SystemRoot%\System32\WindowsPowerShell\v1.0\powershell.exe and the parent process is svchost.exe (TaskScheduler).

• Scenario: Internal Software Deployment via SCCM/Intune

  • Context: During mass software deployments, tools like Microsoft Endpoint Configuration Manager (SCCM) or Microsoft Intune initiate background installation services. These services often download payloads and execute