CommentCrew-threat-apt1

Hunt Hypothesis

CommentCrew-threat-apt1 detects potential adversary behavior involving the use of comment-based PowerShell scripts to execute malicious payloads, which may indicate a low-severity but persistent threat actor leveraging obfuscation techniques. SOC teams should proactively hunt for this behavior in Azure Sentinel to identify and mitigate early-stage compromise attempts that may evade traditional detection methods.

YARA Rule

rule SWORD_APT1
{

    meta:
        author = "AlienVault Labs"
        info = "CommentCrew-threat-apt1"
       
    strings:
        $s1 = "@***@*@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@>>>" wide ascii
        $s2 = "sleep:" wide ascii
        $s3 = "down:" wide ascii
        $s4 = "*========== Bye Bye ! ==========*" wide ascii

    condition:
        all 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 4 string patterns in its detection logic.

• Source Rule

False Positive Guidance

• Scenario: Scheduled system maintenance task using task scheduler
  Filter/Exclusion: process.parent_process_name != "schtasks.exe" or process.name != "schtasks.exe"

• Scenario: Admin performing a database backup using SQL Server Agent Job
  Filter/Exclusion: process.name != "sqlservr.exe" or process.parent_process_name != "sqlagent.exe"

• Scenario: IT staff running a log cleanup script using PowerShell
  Filter/Exclusion: process.name != "powershell.exe" or process.command_line contains "Cleanup-LogFiles.ps1"

• Scenario: User executing a legitimate script for system monitoring using Python
  Filter/Exclusion: process.name != "python.exe" or process.command_line contains "monitoring_script.py"

• Scenario: System update using Windows Update or WSUS
  Filter/Exclusion: process.name != "wuauclt.exe" or process.parent_process_name != "svchost.exe"