CommentCrew-threat-apt1

Hunt Hypothesis

CommentCrew-threat-apt1 detects potential adversary behavior involving suspicious comment creation or modification in Azure resources, which may indicate reconnaissance or persistence activities. SOC teams should proactively hunt for this behavior to identify early-stage adversarial activity and prevent further compromise in their Azure Sentinel environment.

YARA Rule

rule MiniASP
{

    meta:
        author = "AlienVault Labs"
        info = "CommentCrew-threat-apt1"
        
    strings:
        $KEY = { 71 30 6E 63 39 77 38 65 64 61 6F 69 75 6B 32 6D 7A 72 66 79 33 78 74 31 70 35 6C 73 36 37 67 34 62 76 68 6A }
        $PDB = "MiniAsp.pdb" nocase wide ascii

    condition:
        any of them
}

Deployment Notes

This YARA rule can be deployed in the following contexts:

• Microsoft Defender for Endpoint — Custom indicators / advanced hunting
• Email Gateway — Attachment scanning
• File Share Monitoring — Periodic scanning of shared drives
• YARA CLI — Manual threat hunting on endpoints

This rule contains 2 string patterns in its detection logic.

• Source Rule

False Positive Guidance

• Scenario: Scheduled system backup using Veeam Backup & Replication
  Filter/Exclusion: process.name != "vbm" AND process.name != "vbackup.exe"

• Scenario: Admin performing a PowerShell script to clean up temporary files
  Filter/Exclusion: process.name != "powershell.exe" OR process.args NOT LIKE '%Cleanup%'

• Scenario: SQL Server Agent Job running maintenance tasks
  Filter/Exclusion: process.name != "sqlservr.exe" OR process.args NOT LIKE '%SQLAgent -d%'

• Scenario: Windows Task Scheduler executing a legitimate maintenance script
  Filter/Exclusion: process.name != "schtasks.exe" OR process.args NOT LIKE '/RU SYSTEM'

• Scenario: Ansible playbook execution for configuration management
  Filter/Exclusion: process.name != "ansible" OR process.args NOT LIKE '%--become --tags maintenance%'