Remote Management and Monitoring tool - AeroAdmin - File Signature

Hunt Hypothesis

AeroAdmin, a remote management tool, may be used by adversaries to establish persistence or command and control channels by leveraging its file signature for covert communication. SOC teams should proactively hunt for this behavior in Azure Sentinel to detect potential adversary use of RMM tools for long-term access and exfiltration.

KQL Query

let Time_start = now(-5d);
let Time_end = now();
//
DeviceFileCertificateInfo
| where Timestamp between (Time_start..Time_end)
| where Signer has 'AeroAdmin'
| summarize FirstSeen=min(Timestamp), LastSeen=max(Timestamp), 
    Report=make_set(ReportId), Count=count() by DeviceId, DeviceName

Analytic Rule Definition

id: fd1b5c85-1e18-49c1-a21f-ba9484866f27
name: Remote Management and Monitoring tool - AeroAdmin - File Signature
description: |
    Remote Monitoring and Management (RMM) programs are IT to manage remote endpoints. Attackers have begun to abuse these programs to persist or provide C2 channels.
    https://github.com/jischell-msft/RemoteManagementMonitoringTools
requiredDataConnectors:
- connectorId: MicrosoftThreatProtection
  dataTypes:
  - DeviceFileCertificateInfo
tactics: CommandAndControl
relevantTechniques: T1219
query: |
  let Time_start = now(-5d);
  let Time_end = now();
  //
  DeviceFileCertificateInfo
  | where Timestamp between (Time_start..Time_end)
  | where Signer has 'AeroAdmin'
  | summarize FirstSeen=min(Timestamp), LastSeen=max(Timestamp), 
      Report=make_set(ReportId), Count=count() by DeviceId, DeviceName

MITRE ATT&CK Context

• Tactic: CommandAndControl
• Technique: T1219 — T1219

References

• [Source Query](https://github.com/Azure/Azure-Sentinel/blob/main/Hunting Queries/Microsoft 365 Defender/RemoteManagementMonitoring/rmm_AeroAdmin_filesig.yaml)

False Positive Guidance

• Scenario: Legitimate scheduled job for system maintenance using AeroAdmin
  Filter/Exclusion: process.parent_process_name != "AeroAdmin" or process.command_line contains "scheduled_task"

• Scenario: Admin uses AeroAdmin to remotely install a legitimate patch or update
  Filter/Exclusion: process.file_name contains "patch.exe" or process.command_line contains "update"

• Scenario: IT team uses AeroAdmin to monitor system performance and generate reports
  Filter/Exclusion: process.file_name contains "report_generator.exe" or process.command_line contains "generate_report"

• Scenario: System administrator uses AeroMain (the management console for AeroAdmin) to configure remote endpoints
  Filter/Exclusion: process.file_name contains "AeroMain.exe" or process.parent_process_name contains "AeroMain"

• Scenario: Regular file integrity check using AeroAdmin to verify system files
  Filter/Exclusion: process.file_name contains "integrity_check.exe" or process.command_line contains "file_integrity"