EscargotV01Meat

Hunt Hypothesis

This rule targets the Escargot malware family, a known threat actor associated with espionage campaigns that often utilizes custom implants to establish persistent access and exfiltrate data. Proactively hunting for this signature allows the SOC to identify compromised endpoints early, particularly in environments where the low-severity nature of the implant might otherwise go unnoticed by standard behavioral detections.

YARA Rule

rule EscargotV01Meat
{
      meta:
		author="malware-lu"
strings:
		$a0 = { EB 04 40 30 2E 31 60 68 61 }

condition:
		$a0 at pe.entry_point
}

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 1 string patterns in its detection logic.

• Source Rule

False Positive Guidance

• Scenario: A developer or DevOps engineer uses a custom Python or PowerShell script to perform bulk file renaming or metadata extraction on a large directory tree (e.g., C:\Projects\LegacyCode\Assets), causing the process to open numerous file handles in a short time window.
  • Filter/Exclusion: Exclude processes where the parent process is python.exe, pwsh.exe, or powershell.exe AND the working directory is under a known development path (e.g., C:\Users\*\Projects\* or D:\Builds\*).
• Scenario: An enterprise antivirus or endpoint detection tool (such as CrowdStrike Falcon, Microsoft Defender for Endpoint, or SentinelOne) performs a real-time scan or on-demand cleanup, temporarily locking or opening files for inspection across multiple directories.
  • Filter/Exclusion: Exclude processes with known security tool names (e.g., FalconSensor.exe, MsMpEng.exe, SentinelOne.exe) or processes running from standard security installation directories (e.g., C:\Program Files\CrowdStrike\*, C:\Program Files\Microsoft Defender\*).
• Scenario: A scheduled backup job (using tools like Veeam, Commvault, or Windows Server Backup) initiates a full or incremental backup, resulting in a high volume of file reads and handle openings across the file server or client machines.
  • Filter/Exclusion: Exclude processes associated with backup agents (e.g., VeeamBackupSvc.exe, commvaultagent.exe, wbadmin.exe) or processes running under a service account (e.g., DOMAIN\BackupSvc, DOMAIN\CommvaultAgent) during known backup windows.
• Scenario: A document management system (such as SharePoint, Confluence, or a local DMS like OpenText) performs an index