Auto-generated rule on file BluesPortScan.exe

Hunt Hypothesis

This detection identifies potential reconnaissance activity where adversaries execute the BluesPortScan.exe utility to map network topology and identify open ports for lateral movement. Proactively hunting for this behavior in Azure Sentinel is critical because automated port scanning often serves as a precursor to more significant attacks, allowing analysts to validate legitimate administrative tasks against suspicious early-stage threat indicators before they escalate.

YARA Rule

rule BluesPortScan {
	meta:
		description = "Auto-generated rule on file BluesPortScan.exe"
		author = "yarGen Yara Rule Generator by Florian Roth"
		hash = "6292f5fc737511f91af5e35643fc9eef"
	strings:
		$s0 = "This program was made by Volker Voss"
		$s1 = "JiBOo~SSB"
	condition:
		all of them
}

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

Here are 3-5 specific false positive scenarios for the BluesPortScan.exe detection rule, including tailored filters and exclusions:

• Scenario: Scheduled Network Inventory Job

  • Context: The enterprise IT team runs a nightly network inventory using Microsoft System Center Configuration Manager (SCCM) or SolarWinds NPM. These tools often deploy BluesPortScan.exe to all endpoints during the maintenance window (e.g., 02:00 – 04:00) to map open ports and active services.
  • Filter/Exclusion: Create a time-based exclusion allowing execution of C:\Program Files\BluesPortScan\BluesPortScan.exe only between 01:30 and 05:00 on weekdays, or exclude the specific SCCM/SolarWinds service account (e.g., DOMAIN\sccm_service) from triggering this rule.

• Scenario: Endpoint Protection Health Check

  • Context: The organization’s primary EDR solution, such as CrowdStrike Falcon or SentinelOne, utilizes BluesPortScan.exe as a lightweight agent component to perform periodic connectivity checks against the security management server and verify firewall rule integrity.
  • Filter/Exclusion: Add an exclusion based on the parent process. If the parent process of BluesPortScan.exe is identified as FalconSensor.exe, SentinelOneAgent.exe, or WindowsUpdate.exe, suppress the alert, assuming this is a legitimate health check initiated by the security suite itself.

• Scenario: IT Admin Manual Troubleshooting

  • Context: A network administrator logs into a workstation via Remote Desktop Protocol (RDP) to troubleshoot connectivity issues for a specific department. The admin manually launches BluesPortScan.exe from their