VIRUSIWormHybris

Hunt Hypothesis

This rule detects the presence of the Hybris virus or worm, a known threat that can compromise system integrity through file infection or memory execution. Proactively hunting for this signature in Azure Sentinel allows the SOC to identify latent infections early, preventing potential lateral movement or data exfiltration before they escalate into a broader incident.

YARA Rule

rule VIRUSIWormHybris
{
      meta:
		author="malware-lu"
strings:
		$a0 = { EB 16 A8 54 [2] 47 41 42 4C 4B 43 47 43 [6] 52 49 53 ?? FC 68 4C 70 40 ?? FF 15 }

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

• Hybris Managed Build & Deployment Artifacts: During standard CI/CD pipelines, the hybris-build or ant tasks may generate temporary JAR files or intermediate class files in the tmp or build directories that contain specific bytecode patterns or string literals (e.g., “com.hybris”) which the YARA rule might misinterpret as worm-like propagation logic.

  • Filter/Exclusion: Exclude file paths matching */build/*, */tmp/*, or */target/* where the process is java.exe or ant.exe and the parent process is part of the Jenkins/GitLab runner service.

• Hybris Administration Cockpit (Cockpit) Caching: The Hybris Administration Cockpit (ACC) uses in-memory caching and temporary serialization objects for session management. These objects may reside in the hybris/bin/platform/tmp directory and contain serialized Java objects with class names that trigger generic “Java Worm” or “Hybris” YARA signatures if the rule checks for specific class headers or magic bytes.

  • Filter/Exclusion: Exclude files located in C:\hybris\bin\platform\tmp\ or C:\hybris\bin\platform\logs\ when the accessing process is java.exe and the user account is the dedicated hybris-service account.

• Third-Party Plugin Integration (e.g., SAP or Oracle Connectors): Enterprise environments often deploy custom Hybris plugins that embed native C/C++ libraries or specific JARs for database connectivity (e.g., Oracle JDBC, SAP JCo). These binaries may contain strings or code segments that match the YARA rule’s heuristic for “worm-like” behavior (e.g., network socket calls combined with specific string patterns).

  • Filter/Exclusion: Exclude specific known plugin JARs or DLLs by