SDProtector1xRandyLi

Hunt Hypothesis

This detection identifies potential file integrity violations or specific malware signatures associated with the SDProtector1xRandyLi YARA rule within the endpoint ecosystem. Proactively hunting for this behavior in Azure Sentinel allows the SOC team to uncover early-stage threats that may not trigger high-severity alerts, ensuring comprehensive visibility into low-fidelity but potentially significant security events across the environment.

YARA Rule

rule SDProtector1xRandyLi
{
      meta:
		author="malware-lu"
strings:
		$a0 = { 55 8B EC 6A FF 68 1D 32 13 05 68 88 88 88 08 64 A1 00 00 00 00 50 64 89 25 00 00 00 00 58 64 A3 00 00 00 00 58 58 58 58 8B E8 E8 3B 00 00 00 E8 01 00 00 00 FF 58 05 53 00 00 00 51 8B 4C 24 10 89 81 B8 00 00 00 B8 55 01 00 00 89 41 20 33 C0 89 41 04 89 41 }

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 4 specific false positive scenarios for the SDProtector1xRandyLi detection rule, including tailored filters and exclusions:

• Scenario: Automated Antivirus Definition Updates via Microsoft Defender

  • Context: The YARA rule may flag the MsMpEng.exe process when it downloads or installs new virus definition updates. This often involves creating temporary files in the %ProgramData%\Microsoft\Windows Defender\Updates directory that match the signature patterns of the SDProtector tool.
  • Filter/Exclusion: Add a process exclusion for C:\Program Files\Windows Defender\MsMpEng.exe. Additionally, exclude file paths containing \Microsoft\Windows Defender\Updates\ from the rule’s scope to ignore definition update artifacts.

• Scenario: Scheduled System Backup via Veeam Agent

  • Context: During nightly backup windows (e.g., 02:00 AM), VeeamAgent.exe or vssvc.exe creates temporary snapshot files and logs in the C:\ProgramData\Veeam\Backup directory. The rule might misinterpret these high-volume I/O operations and specific file headers as SDProtector deployment activities.
  • Filter/Exclusion: Create a time-based exclusion for the backup window (01:30 AM – 04:30 AM) on endpoints running Veeam. Alternatively, exclude processes named VeeamAgent.exe and paths starting with C:\ProgramData\Veeam\.

• Scenario: Endpoint Configuration Management via SCCM/Intune

  • Context: When System Center Configuration Manager (SCCM) or Microsoft Intune pushes a new application package or configuration policy, the ccmexec.exe process executes scripts that generate temporary installation logs. These logs often contain metadata strings similar to those detected by SDProt