DingBoysPElockPhantasmv08

Hunt Hypothesis

This detection identifies the execution of PE files matching the specific signature of the DingBoys malware family, which is known for employing locking mechanisms and phantasm-like behaviors to evade standard security controls. SOC teams should proactively hunt for this indicator in Azure Sentinel to uncover early-stage infections or dormant threats that may not trigger high-severity alerts but could serve as a precursor to more complex lateral movement or data exfiltration campaigns.

YARA Rule

rule DingBoysPElockPhantasmv08
{
      meta:
		author="malware-lu"
strings:
		$a0 = { 55 57 56 52 51 53 E8 00 00 00 00 5D 8B D5 81 ED 0D 39 40 00 }

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 3-5 specific false positive scenarios for the DingBoysPElockPhantasmv08 detection rule, including suggested filters and exclusions:

• Antivirus Engine Signature Updates (CrowdStrike Falcon / Microsoft Defender)

  • Scenario: The endpoint protection agent periodically downloads and installs new definition updates. These updates often involve the creation of locked PE (Portable Executable) files in temporary directories that exhibit behavior similar to the “phantasm” locking mechanism detected by the rule, specifically when the engine locks a newly downloaded DLL or EXE before scanning it.
  • Filter/Exclusion: Exclude processes named Cnsys.exe (CrowdStrike), MsMpEng.exe, and SecurityHealthService.exe. Additionally, add an exclusion for file paths containing \ProgramData\Microsoft\Windows Defender\Platform\ or \Program Files\CrowdStrike\.

• Scheduled Backup Jobs via Veeam Agent

  • Scenario: During nightly scheduled backup windows, the Veeam Agent locks specific application binaries (such as SQL Server executables) to ensure data consistency. The locking mechanism used by Veeam to prevent file modification during the snapshot process can trigger the PE lock detection logic, appearing as a suspicious phantom lock on critical system files.
  • Filter/Exclusion: Create an exclusion for the process VeeamAgent.exe and VeeamTransportService.exe. Filter alerts where the parent process is Task Scheduler (svchost.exe) running during standard maintenance windows (e.g., 01:00 – 05:00 local time).

• Software Deployment via Microsoft Endpoint Configuration Manager (SCCM)

  • Scenario: When SCCM pushes application updates or patches to endpoints, it utilizes the Windows Installer service (msiexec.exe) which often locks PE files during