SVKProtectorv111

Hunt Hypothesis

This hunt hypothesis targets adversaries utilizing the SVKProtectorv111 signature to identify potentially malicious or suspicious software artifacts that may evade standard detection thresholds. Proactive hunting for this YARA rule in Azure Sentinel is essential to uncover low-severity indicators of compromise early, ensuring that stealthy threats are investigated before they escalate into significant incidents.

YARA Rule

rule SVKProtectorv111
{
      meta:
		author="malware-lu"
strings:
		$a0 = { 60 E8 [4] 5D 81 ED 06 [3] 64 A0 23 }

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 SVKProtectorv111 detection rule, including suggested filters and exclusions:

• Antivirus Engine Scanning of Compressed Archives

  • Scenario: The enterprise endpoint protection suite (e.g., CrowdStrike Falcon or Microsoft Defender) performs scheduled deep scans on large .zip or .7z archives containing software installers. The YARA rule may misinterpret the internal structure and encryption signatures of these compressed files as malicious SVKProtector behavior, triggering alerts during nightly maintenance windows.
  • Filter/Exclusion: Create a process exclusion for C:\Program Files\Microsoft Defender\MsMpEng.exe (or equivalent AV engine binary) when the target file extension is .zip, .7z, or .rar. Additionally, suppress alerts if the parent process is identified as a scheduled task (Task Scheduler) running during off-hours (e.g., 02:00–04:00 local time).

• Software Deployment via Configuration Management Tools

  • Scenario: During routine patching cycles, tools like Microsoft Endpoint Configuration Manager (SCCM) or Ansible Tower deploy application updates. These tools often extract and execute installer packages that utilize SVKProtector-like signatures for integrity verification, causing the rule to flag legitimate deployment agents as suspicious processes initiating new file writes.
  • Filter/Exclusion: Exclude alerts where the parent process name matches ccmexec.exe (SCCM) or ansible-runner, and the execution path resides within standard system directories such as C:\Windows\CCM\ or D:\Ansible\. A filter can also be applied to ignore events where the file hash matches a known “Golden Image” baseline stored in the SIEM.

• Database Backup Jobs Executing via PowerShell