ThreatFox: DCRat IOCs

Hunt Hypothesis

This hunt targets adversaries deploying the DCRat remote access trojan to establish persistent command-and-control channels and exfiltrate sensitive data following initial phishing or drive-by compromise. Proactively hunting these specific IOCs in Azure Sentinel is critical to rapidly identify early-stage infections before attackers can leverage their full remote execution capabilities for lateral movement and data theft.

IOC Summary

Malware Family: DCRat Total IOCs: 2 IOC Types: ip:port, url

KQL: Ip Hunt

// Hunt for network connections to known malicious IPs
// Source: ThreatFox - DCRat
let malicious_ips = dynamic(["91.92.47.95"]);
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(["91.92.47.95"]);
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://keutbdump3.temp.swtest.ru/pipePhpjsPacketLongpoll.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 4 specific false positive scenarios for the ThreatFox: DCRat IOCs detection rule in an enterprise environment, including suggested filters or exclusions:

• Endpoint Protection Management Console Traffic

  • Scenario: The organization uses a centralized Endpoint Detection and Response (EDR) solution (e.g., CrowdStrike Falcon, Microsoft Defender for Endpoint, or SentinelOne). These agents frequently communicate with the management console over specific IP addresses and ports to receive policy updates, upload telemetry, or download definition signatures. If the EDR vendor’s cloud infrastructure shares an IP address listed in the DCRat IOC set, legitimate heartbeat or update traffic will trigger the alert.
  • Filter/Exclusion: Create a whitelist rule excluding outbound connections from the Endpoint Agent service (e.g., C:\Program Files\CrowdStrike\fs.exe) to the specific IP:Port combination associated with the EDR vendor’s cloud region, provided the destination port matches standard management ports (e.g., 443, 8080).

• Automated Patch Management and Software Distribution

  • Scenario: IT administrators utilize tools like SCCM (Microsoft Endpoint Configuration Manager), Ivanti, or Jamf to push software updates and patches. These scheduled jobs often download large payloads from internal distribution points or external vendor repositories that may host the DCRat IOC IP. For instance, a nightly job running via Task Scheduler might initiate an HTTPS connection to a vendor’s update server (e.g., Adobe Creative Cloud Updater or Zoom Auto-Update) which coincidentally resolves to the flagged IP.
  • Filter/Exclusion: Exclude traffic originating from known patch management executables (e.g., ccmexec.exe, jamfagent.exe) during standard business hours or specific maintenance windows (e.g., 02:00–04:00 UTC).