IndiaBravo generic

Hunt Hypothesis

This detection targets the execution of artifacts associated with the IndiaBrovo threat actor, which may indicate early-stage reconnaissance or lateral movement activities within the environment. Proactive hunting for this signature in Azure Sentinel is essential to validate its presence before it escalates into a higher-severity incident, ensuring that low-fidelity signals are not overlooked during routine monitoring.

YARA Rule

rule IndiaBravo_generic
{
	meta:
		copyright = "2015 Novetta Solutions"
		author = "Novetta Threat Research & Interdiction Group - trig@novetta.com"

	strings:
		$extractDll = "[2] - Extract Dll..." wide
		$createSvc = "[3] - CreateSVC..." wide

	condition:
		all of them
	
}

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 2 string patterns in its detection logic.

• Source Rule

False Positive Guidance

Here are 4 specific false positive scenarios for the IndiaBravo_generic detection rule in an enterprise environment, including suggested filters and exclusions:

• Scenario: Enterprise Antivirus Real-Time Scanning of Legacy Archives

  • Context: The IndiaBravo malware often mimics legitimate file extraction behaviors. In environments using Microsoft Defender for Endpoint or Symantec Endpoint Protection, the real-time protection engine frequently scans and extracts large legacy .zip or .cab archives containing software installers (e.g., Adobe Creative Cloud updates) stored in network shares. The YARA rule may flag the temporary extraction process as suspicious activity similar to IndiaBravo’s payload delivery mechanism.
  • Suggested Filter/Exclusion: Create a path-based exclusion for known application data directories (e.g., C:\ProgramData\Microsoft\Windows Defender\Platform\* or specific network share paths like \\FileServer\Software_Deployments). Additionally, exclude processes running under the context of the AV service itself (e.g., MsMpEng.exe, Symantec Antivirus.exe) from triggering this rule.

• Scenario: Scheduled PowerShell Script Execution for Patch Management

  • Context: IT Operations teams often utilize PowerShell scripts scheduled via Task Scheduler to distribute patches or configuration updates across the fleet. These scripts frequently download binaries, decompress them into temporary folders (%TEMP%), and execute installers—a behavior pattern that closely matches IndiaBravo’s execution chain. If the script uses standard tools like 7-Zip or native PowerShell cmdlets for file manipulation, the YARA rule may misinterpret these legitimate administrative tasks as malicious deployment activities.
  • Suggested Filter/Exclusion: Implement a hash-based exclusion list for known good scripts and their associated executables (e.g., powershell.exe, 7zFM.exe). Configure the