VxEddiebased1745

Hunt Hypothesis

This rule detects the presence of the VxEddiebased1745 YARA signature, which likely identifies a specific low-severity malware variant or suspicious code pattern within memory or disk artifacts. Proactively hunting for this indicator allows the SOC team to identify early-stage infections or dormant threats in Azure Sentinel that may not yet trigger high-fidelity alerts, enabling faster containment before lateral movement occurs.

YARA Rule

rule VxEddiebased1745
{
      meta:
		author="malware-lu"
strings:
		$a0 = { E8 [2] 5E 81 EE [2] FC ?? 2E [4] 4D 5A [2] FA ?? 8B E6 81 [3] FB ?? 3B [5] 50 06 ?? 56 1E 8B FE 33 C0 ?? 50 8E D8 }

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 Visual Studio Code or JetBrains Rider to edit a C# or C++ project where the source code contains the literal string VxEddiebased1745 as a variable name, constant, or comment.
  • Filter/Exclusion: Exclude files with extensions .cs, .cpp, .h, .java, or .py located in standard source code directories (e.g., src\, code\, projects\) unless the file size is larger than 1MB (to distinguish from compiled binaries).
• Scenario: An IT administrator runs a PowerShell script or CMD batch file to perform a system audit or log cleanup, where the string VxEddiebased1745 is used as a unique identifier in a log file path, a temporary directory name, or a registry key value for tracking a specific maintenance window.
  • Filter/Exclusion: Exclude processes named powershell.exe, pwsh.exe, or cmd.exe if the parent process is explorer.exe or taskeng.exe (Task Scheduler) and the working directory is under C:\Windows\Temp\ or C:\ProgramData\.
• Scenario: A SQL Server or Oracle database administrator executes a backup or restore job where the backup file name or a table column name includes VxEddiebased1745 as part of a naming convention for a specific client or project code.
  • Filter/Exclusion: Exclude files with extensions .bak, .trn, .mdf, or .ldf located in standard SQL data directories (e.g., C:\Program Files\Microsoft SQL Server\...\Data\).
• Scenario: A Java or .NET application is