EXEShieldV05Smoke

Hunt Hypothesis

This hypothesis targets the presence of EXEShield, a commercial executable protection tool, which adversaries may leverage to obfuscate malicious payloads and evade static analysis. Proactively hunting for this indicator in Azure Sentinel helps identify potentially compromised endpoints where attackers are using commercial packers to hide their code, even though the low severity suggests it may be a benign artifact.

YARA Rule

rule EXEShieldV05Smoke
{
      meta:
		author="malware-lu"
strings:
		$a0 = { E8 04 00 00 00 83 60 EB 0C 5D EB 05 45 55 EB 04 B8 EB F9 00 C3 E8 00 00 00 00 5D 81 ED BC 1A 40 00 EB 01 00 8D B5 46 1B 40 00 BA B3 0A 00 00 EB 01 00 8D 8D F9 25 40 00 8B 09 E8 14 00 00 00 83 EB 01 00 8B FE E8 00 00 00 00 58 83 C0 07 50 C3 00 EB 04 58 40 }
	$a1 = { E8 04 00 00 00 83 60 EB 0C 5D EB 05 45 55 EB 04 B8 EB F9 00 C3 E8 00 00 00 00 5D 81 ED BC 1A 40 00 EB 01 00 8D B5 46 1B 40 00 BA B3 0A 00 00 EB 01 00 8D 8D F9 25 40 00 8B 09 E8 14 00 00 00 83 EB 01 00 8B FE E8 00 00 00 00 58 83 C0 07 50 C3 00 EB 04 58 40 50 C3 8A 06 46 EB 01 00 D0 C8 E8 14 00 00 00 83 EB 01 00 2A C2 E8 00 00 00 00 5B 83 C3 07 53 C3 00 EB 04 5B 43 53 C3 EB 01 00 32 C2 E8 0B 00 00 00 00 32 C1 EB 01 00 C0 C0 02 EB 09 2A C2 5B EB 01 00 43 53 C3 88 07 EB 01 00 47 4A 75 B4 90 }

condition:
		$a0 at pe.entry_point or $a1 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 2 string patterns in its detection logic.

• Source Rule

False Positive Guidance

• Scenario: Execution of the EXEShieldV05Smoke binary (or its associated smoke test utility) by the IT Operations team during a scheduled Windows Update maintenance window to verify that the EXEShield agent is functioning correctly on a sample of endpoints.
  • Filter/Exclusion: Exclude events where the parent process is powershell.exe or cmd.exe and the command line contains specific smoke test arguments (e.g., /smoke, /test, or /verify) and the user account belongs to the IT_Ops_Svc or Maintenance_Account security group.
• Scenario: The DevOps team runs the smoke test binary as part of a CI/CD pipeline on a build agent or CI runner (e.g., Azure DevOps Agent, Jenkins Node) to validate the EXEShield integration before deploying new application packages.
  • Filter/Exclusion: Exclude detections originating from hosts tagged with Role=CI_Builder or Role=DevOps_Agent in your CMDB or asset inventory, or where the parent process is node.exe, java.exe, or msbuild.exe typical of build systems.
• Scenario: A System Administrator manually executes the smoke test on a newly imaged workstation during the Golden Image refresh process to confirm the EXEShield driver loads correctly before the machine is added to the domain.
  • Filter/Exclusion: Exclude events where the user account is a local admin account (e.g., LocalAdmin, ImageAdmin) and the machine has been online for less than 24 hours, or where the parent process is explorer.exe and the working directory is a temporary staging folder (e.g., C:\Temp\, C:\Staging\).
• Scenario: The