ThreatFox: Remus IOCs

Hunt Hypothesis

The Remus malware is likely exfiltrating sensitive data and establishing persistence through suspicious network activity and file system modifications. SOC teams should proactively hunt for these behaviors in Azure Sentinel to detect and mitigate advanced persistent threats before significant data loss occurs.

IOC Summary

Malware Family: Remus Total IOCs: 2 IOC Types: domain

KQL: Domain Hunt

// Hunt for DNS queries to known malicious domains
// Source: ThreatFox - Remus
let malicious_domains = dynamic(["mythicsu.biz", "cheapoca.biz"]);
DnsEvents
| where Name has_any (malicious_domains)
| project TimeGenerated, Computer, Name, IPAddresses, QueryType
| order by TimeGenerated desc

Required Data Sources

References

• ThreatFox — Remus

False Positive Guidance

• Scenario: Legitimate System Monitoring Tool Usage
  Description: A security tool like OSSEC or Splunk is configured to monitor system logs and generates alerts for unusual activity, which may be flagged by the Remus IOC detection rule.
  Filter/Exclusion: Exclude events where the source is a known security monitoring tool (e.g., source == "OSSEC") or where the event is part of a configured log analysis rule.

• Scenario: Scheduled Administrative Task
  Description: A scheduled task using Task Scheduler (e.g., schtasks.exe) is running a legitimate maintenance script that matches the IOC pattern (e.g., remus.exe or remus.dll).
  Filter/Exclusion: Exclude processes initiated by the Task Scheduler service (service_name == "Schedule") or where the process is associated with a known administrative task (e.g., C:\Windows\System32\schedtasks.exe).

• Scenario: Software Update or Patch Deployment
  Description: A patch management tool like Microsoft System Center Configuration Manager (SCCM) or Ansible is deploying a software update that includes a file matching the Remus IOC.
  Filter/Exclusion: Exclude events where the file is part of a known patch or update (e.g., file_path contains "Microsoft" or "Ansible") or where the process is initiated by a patch management service.

• Scenario: Network Monitoring Tool Traffic
  Description: A network monitoring tool like Wireshark or tcpdump is capturing traffic that includes data exfiltration patterns similar to those seen in Remus.
  Filter/Exclusion: Exclude traffic originating from or destined to a known network monitoring tool (e.g., process_name == "Wireshark") or traffic that is