MoleBoxv254Teggo

Hunt Hypothesis

This rule detects the presence of MoleBox, a lightweight Windows sandboxing tool frequently used by adversaries to execute and test malicious payloads in an isolated environment to evade host-based detection. Proactively hunting for this artifact in Azure Sentinel allows the SOC team to identify potential staging or testing activities that may precede a full compromise, particularly when combined with other indicators of suspicious process execution or file creation.

YARA Rule

rule MoleBoxv254Teggo
{
      meta:
		author="malware-lu"
strings:
		$a0 = { 00 8B 4D F0 8B 11 89 15 [3] 00 8B 45 FC A3 [3] 00 5F 5E 8B E5 5D C3 CC CC CC E8 EB FB FF FF 58 E8 ?? 07 00 00 58 89 44 24 24 61 58 58 FF D0 E8 [2] 00 00 6A 00 FF 15 [3] 00 CC CC CC CC CC CC CC CC CC CC CC CC CC CC }

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

• Antivirus/EDR Signature Update Scans: When enterprise endpoint protection platforms (e.g., Microsoft Defender for Endpoint, CrowdStrike Falcon, or SentinelOne) perform periodic full-system scans or update their signature databases, they may load or execute YARA rule files (including MoleBoxv254Teggo.yar) into memory or temporary directories. This can trigger file-based or memory-based YARA detections if the rule is scanned against the rule file itself or its compiled binary.

  • Filter/Exclusion: Exclude processes from known EDR/AV service executables (e.g., MsMpEng.exe, FalconSensor.exe, SentinelOneAgent.exe) or exclude file paths under standard AV update directories (e.g., C:\ProgramData\Microsoft\Windows Defender\, C:\ProgramData\CrowdStrike\) from YARA scanning triggers.

• Security Team YARA Rule Testing/Validation: SOC or threat hunting analysts often use tools like yara CLI, YARA-Native, or GUI tools (e.g., YARA-GUI, VirusTotal YARA scanner) to test new or updated rules against known good/bad samples. If the MoleBoxv254Teggo rule is loaded into a testing environment or scanned against a corpus of benign files, it may generate alerts if the rule matches a benign test file or if the rule file itself is scanned.

  • Filter/Exclusion: Exclude processes associated with YARA testing tools (e.g., yara.exe, yarac.exe, yara-gui.exe) and exclude user profiles or directories designated for threat hunting (e.g., C:\Users\<analyst>\ThreatHunting\, C:\Temp\YaraTests\) from detection triggers.

• CI/CD Pipeline Security Scanning: In Dev