VMProtect106107PolyTech

Hunt Hypothesis

This YARA rule targets specific VMProtect-packed binaries, indicating the presence of obfuscated executables that adversaries often use to hide malicious logic and evade static analysis. Proactively hunting for these signatures in Azure Sentinel allows the SOC to identify potentially compromised workstations or servers where attackers have deployed packed payloads to establish persistence or execute stealthy operations.

YARA Rule

rule VMProtect106107PolyTech
{
      meta:
		author="malware-lu"
strings:
		$a0 = { 9C 60 68 00 00 00 00 8B 74 24 28 BF [4] FC 89 F3 03 34 24 AC 00 D8 }

condition:
		$a0
}

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

• Legacy Application Compatibility Patches: Older versions of enterprise software (e.g., specific builds of Adobe Creative Suite, AutoCAD, or legacy ERP clients) often use VMProtect to obfuscate licensing checks or anti-debugging routines. When these applications are updated or re-deployed via SCCM/Intune, the protected binaries may be written to disk or loaded into memory, triggering the YARA signature.

  • Filter/Exclusion: Exclude files located in standard vendor installation directories (e.g., C:\Program Files\Adobe\, C:\Program Files\Autodesk\) where the executable name matches known legacy application binaries (e.g., acrord32.exe, acad.exe).

• Virtual Machine Snapshot and Backup Agents: Hypervisor backup solutions (e.g., Veeam, Commvault) or snapshot utilities may create temporary copies or restore points of guest OS files. If a protected binary is being read from the guest disk and written to the backup agent’s staging area or temporary folder on the host, the YARA scan of the file content may match the VMProtect signature.

  • Filter/Exclusion: Exclude file paths containing backup agent specific directories (e.g., \Veeam\Backup\, \Commvault\Temp\) or files with extensions associated with backup archives (e.g., .vbk, .dat) during the backup window.

• Container Image Layer Extraction: In CI/CD pipelines or containerized environments (e.g., Docker, Kubernetes), base images or application layers may contain VMProtect-protected binaries (common in commercial Java/.NET applications or proprietary microservices). When these layers are pulled and extracted to the node’s local storage (e.g., /var/lib/docker/overlay2/ or /var/lib/containerd/), the file system scan may detect the signature.

  • Filter/Exclusion: Exclude