DAEMONProtectv067

Hunt Hypothesis

This detection identifies potential malicious daemon processes leveraging specific YARA signatures to uncover stealthy persistence mechanisms that may evade standard signature-based defenses. Proactively hunting for these indicators in Azure Sentinel allows the SOC team to validate false positives and identify early-stage compromise attempts before they escalate into significant incidents, despite the current low severity rating.

YARA Rule

rule DAEMONProtectv067
{
      meta:
		author="malware-lu"
strings:
		$a0 = { 60 60 9C 8C C9 32 C9 E3 0C 52 0F 01 4C 24 FE 5A 83 C2 0C 8B 1A 9D 61 }

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 DAEMONProtectv067 detection rule, including suggested filters and exclusions:

• Scenario: Scheduled Windows Update Deployment via WSUS

  • Context: The wuauserv (Windows Update) service initiates a background download or installation task during business hours, triggering the YARA signature due to its interaction with system daemon processes.
  • Filter/Exclusion: Exclude process paths containing C:\Windows\System32\wuauclt.exe and C:\Windows\System32\usoc.dll. Additionally, add a time-based filter to suppress alerts between 08:00–17:00 UTC on weekdays if the user context is SYSTEM.

• Scenario: Microsoft Defender Antivirus Real-Time Scanning

  • Context: The MsMpEng.exe process performs real-time scanning of a large log file or database, spawning child processes that mimic the behavior pattern defined in DAEMONProtectv067.
  • Filter/Exclusion: Create an exclusion for the parent process C:\Program Files\Microsoft Defender Antivirus\bin\MsMpEng.exe. If the rule detects specific hash signatures known to Microsoft’s engine, apply a whitelist based on the file SHA-256 hash of the core engine binaries.

• Scenario: Enterprise Backup Job (Veeam or Commvault)

  • Context: A nightly backup agent (e.g., VeeamTransportService.exe or CommServe.exe) launches a daemon to index files, triggering the rule due to high I/O and process spawning typical of backup operations.
  • Filter/Exclusion: Exclude processes running under the specific service account used for backups (e.g., DOMAIN\BackupSvc). Filter out alerts where the command line contains keywords like “backup