VxPredator2448

Hunt Hypothesis

This hypothesis targets the presence of the VxPredator2448 malware family, a known threat actor often associated with advanced persistent threats and data exfiltration campaigns. Proactively hunting for this signature in Azure Sentinel allows the SOC to identify compromised endpoints or cloud assets early, mitigating the risk of lateral movement or data leakage before the adversary achieves their objective.

YARA Rule

rule VxPredator2448
{
      meta:
		author="malware-lu"
strings:
		$a0 = { 0E 1F BF [2] B8 [2] B9 [2] 49 [4] 2A C1 4F 4F [2] F9 CC }

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

• Scenario: A legacy Java-based enterprise application (e.g., an internal HR portal or financial reporting tool) is deployed via a standard MSI installer that includes a generic java.exe or jre binary in its installation directory. The YARA rule likely matches on specific byte patterns or string constants common in older JRE builds or specific Java agent libraries bundled with the app.

  • Filter/Exclusion: Exclude files located in specific application directories (e.g., C:\Program Files\InternalHR\jre\bin\) or exclude files with a specific version hash if the rule is known to match a specific JRE build. Alternatively, exclude based on the parent process being the application’s main executable (e.g., hrapp.exe) rather than a generic system process.

• Scenario: A scheduled maintenance job using a third-party backup or archiving tool (e.g., Veeam, Commvault, or Acronis) creates temporary cache files or metadata blobs in a temp directory (%TEMP% or C:\ProgramData\Vendor\Temp) that contain embedded signatures or headers matching the VxPredator2448 pattern. These are often legitimate binary structures used for deduplication or compression.

  • Filter/Exclusion: Exclude files with specific extensions (e.g., .vbk, .dat, .tmp) located in vendor-specific temp directories. Add an exclusion for paths containing \ProgramData\ or \Temp\ if the rule is not designed to catch fileless or temp-file-based threats, or refine the YARA rule to require the presence of a specific malicious string in addition to the structural match.

• Scenario: A developer or IT admin runs a local instance of a database or message queue service (e.g., PostgreSQL, Redis, or RabbitMQ) on a jump box or dev server. The service writes log files or