Packman0001Bubbasoft

Hunt Hypothesis

This hunt hypothesis targets the presence of the “Packman0001Bubbasoft” component identified by a specific YARA signature to detect potential software supply chain anomalies or benign third-party integrations that may be misclassified. Proactively hunting for this indicator in Azure Sentinel allows the SOC team to validate its legitimacy and distinguish it from malicious packer behaviors, ensuring low-severity alerts do not obscure critical threats within the environment.

YARA Rule

rule Packman0001Bubbasoft
{
      meta:
		author="malware-lu"
strings:
		$a0 = { 0F 85 ?? FF FF FF 8D B3 [4] EB 3D 8B 46 0C 03 C3 50 FF 55 00 56 8B 36 0B F6 75 02 8B F7 03 F3 03 FB EB 1B D1 C1 D1 E9 73 05 0F B7 C9 EB 05 03 CB 8D 49 02 50 51 50 FF 55 04 AB 58 83 C6 04 8B 0E 85 C9 75 DF 5E 83 C6 14 8B 7E 10 85 FF 75 BC 8D 8B 00 }

condition:
		$a0
}

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 Packman0001Bubbasoft detection rule, along with targeted filtering strategies suitable for an enterprise environment:

• Scenario: Automated Deployment via Microsoft Endpoint Configuration Manager (SCCM/MECM)

  • Context: The IT operations team uses SCCM to push a standardized software package containing the BubbaSoft suite to 500+ workstations during a nightly maintenance window. The deployment agent extracts and executes the installer, which matches the YARA signature for Packman0001Bubbasoft.
  • Filter/Exclusion: Create an exclusion based on the Process Name (ccmsetup.exe or wuauserv.exe) and Parent Process. Configure the rule to ignore alerts where the parent process is a known deployment agent running under the system account (e.g., NT AUTHORITY\SYSTEM).

• Scenario: Scheduled Group Policy Software Installation

  • Context: A Group Policy Object (GPO) is configured to install BubbaSoft utilities on user machines upon login or at specific intervals. The GPO engine (gpupdate.exe or msiexec.exe) triggers the installation logic, causing the YARA rule to flag the execution of the installer binary as a potential threat.
  • Filter/Exclusion: Implement a filter based on Process Command Line. Exclude events where the command line contains flags typical of GPO installations (e.g., /quiet, /norestart) and is executed by msiexec.exe with a specific package GUID associated with the BubbaSoft deployment.

• Scenario: Endpoint Protection Quarantine Scanning

  • Context: The organization’s primary EDR solution (e.g., CrowdStrike Falcon or Microsoft Defender for Endpoint) performs real-time scanning of the `C:\Program Files\Bubbas