AlexProtectorv10Alex

Hunt Hypothesis

This detection identifies the presence of the AlexProtectorv10Alex signature within endpoint logs to uncover potential legacy or specialized security software artifacts that may indicate a targeted deployment or an unrecognized third-party agent. A proactive hunt is essential in Azure Sentinel to validate whether these instances represent authorized tools or anomalous behaviors that could obscure visibility into genuine adversary activity on the network.

YARA Rule

rule AlexProtectorv10Alex
{
      meta:
		author="malware-lu"
strings:
		$a0 = { 60 E8 00 00 00 00 5D 81 ED 06 10 40 00 E8 24 00 00 00 EB 01 E9 8B }

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

Here are 5 specific false positive scenarios for the AlexProtectorv10Alex detection rule, including suggested filters and exclusions tailored for an enterprise environment:

• Scenario: Automated Endpoint Protection Scans by CrowdStrike Falcon

  • Context: The YARA rule triggers when the CrowdStrike Falcon sensor performs its scheduled daily deep scan of the C:\Program Files directory. The scanner process (csagent.exe) loads a dynamic library that matches the signature pattern defined in AlexProtectorv10Alex, mistaking the security tool’s own payload for a potential threat.
  • Suggested Filter: Exclude alerts where the parent process is csagent.exe (CrowdStrike Falcon) and the file path contains \Program Files\CrowdStrike\.

• Scenario: Microsoft System Center Configuration Manager (SCCM) Software Deployment

  • Context: During a scheduled maintenance window, SCCM pushes a new application package to workstations. The deployment agent (ccmsetup.exe) extracts and installs files that contain the specific byte sequence or header structure targeted by the rule, causing a high volume of alerts during the deployment phase (typically 02:00–04:00 UTC).
  • Suggested Filter: Create an exclusion for events occurring between 01:00 and 05:00 local time where the process name is ccmsetup.exe or WUAHandler.exe, provided the file hash matches a known good deployment artifact.

• Scenario: Java Runtime Environment (JRE) Auto-Updates

  • Context: The Java Update Service (jusched.exe) runs in the background to check for and apply security patches. When it downloads and unpacks a new JRE version, the temporary extraction of .jar files triggers the YARA rule due to shared code signatures within the archive structure