EPack14litefinalby6aHguT

Hunt Hypothesis

This detection identifies potential malicious activity associated with the specific YARA signature “EPack14litefinalby6aHguT,” which may indicate the presence of a known or emerging threat package within the environment. Although currently flagged as low severity, proactively hunting for this indicator in Azure Sentinel allows the SOC team to validate its context and prevent potential escalation before it impacts critical assets.

YARA Rule

rule EPack14litefinalby6aHguT
{
      meta:
		author="malware-lu"
strings:
		$a0 = { 33 C0 8B C0 68 [4] 68 [4] E8 }

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 detection rule EPack14litefinalby6aHguT, along with targeted filters and exclusions:

• Scenario: Scheduled Antivirus Definition Updates

  • Context: The enterprise endpoint protection agent (e.g., Microsoft Defender or CrowdStrike) automatically downloads and installs new virus definition packs during off-hours. These updates often involve unpacking compressed archives containing executable payloads that match the signature logic of EPack14litefinalby6aHguT.
  • Filter/Exclusion: Exclude processes named mpcmdrun.exe (Microsoft Defender) or csagent.exe (CrowdStrike) when they are spawned by the Windows Update service (svchost.exe) between 02:00 and 04:00 local time.

• Scenario: Enterprise Software Deployment via SCCM

  • Context: The IT operations team uses Microsoft Endpoint Configuration Manager (SCCM) to push a new application patch. The deployment agent extracts the installer package from a compressed .msi or .cab file, triggering the YARA rule on the temporary extraction folder before the installation begins.
  • Filter/Exclusion: Create an exclusion for any process tree rooted under ccmsetup.exe (Configuration Manager Setup) where the working directory contains \Temp\Deployment and the file extension is .exe or .dll.

• Scenario: Automated Backup and Archiving Jobs

  • Context: A nightly backup job using Veeam Agent for Windows compresses critical database logs into a proprietary archive format. The rule detects the unpacking of these archives as a potential “packer” activity, mistaking the legitimate archiving process for a suspicious executable packer.
  • Filter/Exclusion: Exclude alerts where the parent process is `veeamagent.exe