yodasProtector102103AshkbizDanehkar

Hunt Hypothesis

This detection identifies potential malicious file activity matching the specific signature of the “yodasProtector102103AshkbizDanehkar” YARA rule, which may indicate the presence of a targeted threat or known malware variant within the environment. Proactive hunting for this indicator in Azure Sentinel is essential to validate its context and ensure that low-severity alerts do not overlook early-stage compromise signals that could evolve into significant incidents if left uninvestigated.

YARA Rule

rule yodasProtector102103AshkbizDanehkar
{
      meta:
		author="malware-lu"
strings:
		$a0 = { E8 03 00 00 00 EB 01 ?? BB 55 00 00 00 E8 03 00 00 00 EB 01 ?? E8 8F 00 00 00 E8 03 00 00 00 EB 01 ?? E8 82 00 00 00 E8 03 00 00 00 EB 01 ?? E8 B8 00 00 00 E8 03 00 00 00 EB 01 ?? E8 AB 00 00 }

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

Here are 4 specific false positive scenarios for the yodasProtector102103AshkbizDanehkar detection rule in an enterprise environment:

• Scenario: The YARA signature flags a legitimate deployment of Microsoft Office updates (e.g., OfficeC2RClient.exe) when the update installer extracts temporary CAB files containing embedded scripts that match the “Ashkbiz” pattern.

  • Filter/Exclusion: Create an exclusion rule for processes running under the path C:\Program Files\Microsoft Office* and specifically targeting OfficeC2RClient.exe, excluding any file hashes associated with the current Office version update package.

• Scenario: A scheduled nightly backup job executed by Veeam Backup & Replication triggers the rule when it scans and archives a large database dump, as the compression engine generates temporary binary artifacts that mimic the detection logic’s byte sequence.

  • Filter/Exclusion: Exclude alerts generated by the service account DOMAIN\VeeamBackupSvc when the process name is Veeam.Backup.Service.exe, specifically during the defined maintenance window (e.g., 02:00–04:00 daily).

• Scenario: The rule detects a false positive during the execution of Sysinternals Process Explorer (ProcExp.exe) by an administrator who is manually analyzing a suspicious process, as the tool’s internal DLL injection mechanism triggers the YARA signature.

  • Filter/Exclusion: Add a whitelist entry for C:\Program Files\Sysinternals Suite\ProcExp.exe and exclude any child processes spawned directly by this executable within a 5-minute window of its launch.

• Scenario: An automated Ansible playbook runs on the endpoint to push configuration changes, utilizing a custom Python script that embeds a specific encryption library matching the rule’s