PolyCryptPE214b215JLabSoftwareCreationshoep

Hunt Hypothesis

This detection identifies the presence of a specific polymorphic executable associated with JLab Software Creations, which may indicate an adversary employing code mutation techniques to evade signature-based defenses. Proactive hunting for this behavior in Azure Sentinel is essential to validate whether these legitimate artifacts are being leveraged as a cover for malicious activity or represent a new threat vector requiring deeper behavioral analysis.

YARA Rule

rule PolyCryptPE214b215JLabSoftwareCreationshoep
{
      meta:
		author="malware-lu"
strings:
		$a0 = { 91 8B F4 AD FE C9 80 34 08 ?? E2 FA C3 60 E8 ED FF FF FF EB }

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

Here are 3-5 specific false positive scenarios for the PolyCryptPE214b215JLabSoftwareCreationshoep detection rule, including suggested filters and exclusions:

• Scenario: Scheduled Antivirus Definition Updates

  • Context: The YARA rule likely matches a generic PE (Portable Executable) structure common in security vendors. In an enterprise environment, the daily scheduled update of Microsoft Defender for Endpoint or Symantec Endpoint Protection often involves downloading and executing a new definition package that shares similar cryptographic signatures or header structures with the detection logic.
  • Suggested Filter/Exclusion: Add a file path exclusion for the specific vendor’s installation directory (e.g., C:\Program Files\Microsoft Defender\ or C:\ProgramData\Symantec) and exclude processes named MpCmdRun.exe or Rtvscan64.exe when they are running under the SYSTEM account.

• Scenario: Corporate Software Deployment via SCCM/Intune

  • Context: When Microsoft Endpoint Configuration Manager (SCCM) or Microsoft Intune pushes a new application package to endpoints, the deployment engine (ccmsetup.exe or IntuneManagementExtension) often extracts and executes installer packages that utilize the same PE header characteristics flagged by this rule. This is common during mass rollouts of internal line-of-business applications.
  • Suggested Filter/Exclusion: Create a process exclusion for ccmexec.exe, CcmSetup.exe, and IntuneManagementExtension.exe. Additionally, filter out events where the parent process is one of these deployment agents to distinguish between the installer itself and the payload it extracts.

• Scenario: Automated Backup and Archiving Jobs

  • Context: Enterprise backup solutions like Veeam Agent for Windows, **Acronis