Nakedbind10nakedcrew

Hunt Hypothesis

This detection identifies potential malicious activity associated with the “Nakedbind10nakedcrew” signature, which may indicate an adversary utilizing specific file-based indicators to establish a foothold or execute initial payloads within the environment. Proactively hunting for this behavior in Azure Sentinel allows the SOC team to uncover low-severity anomalies that could represent early-stage threats, ensuring timely investigation before they escalate into more significant incidents.

YARA Rule

rule Nakedbind10nakedcrew
{
      meta:
		author="malware-lu"
strings:
		$a0 = { 64 8B 38 48 8B C8 F2 AF AF 8B 1F 66 33 DB 66 81 3B 4D 5A 74 08 81 EB 00 00 }

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

Here are 4 specific false positive scenarios for the Nakedbind10nakedcrew detection rule, including suggested filters and exclusions:

• Scenario: Microsoft Defender Antivirus Scheduled Scans

  • Context: The YARA rule often triggers on the MsMpEng.exe process when it performs its daily “Quick Scan” or “Full Scan,” specifically when scanning network shares or mapped drives where the rule detects a specific binary signature pattern resembling the target threat.
  • Suggested Filter/Exclusion: Create an exclusion in the detection logic to ignore events where the ProcessName is MsMpEng.exe AND the CommandLine contains /scan. Alternatively, add C:\Program Files\Windows Defender\MsMpEng.exe to the process whitelist.

• Scenario: SCCM (Endpoint Configuration Manager) Software Updates

  • Context: During scheduled maintenance windows, the SCCM client (ccmexec.exe) downloads and installs patches or applications. The rule may flag the temporary extraction of update packages in the C:\Windows\CCMCache directory as a potential “naked” binding event due to the rapid creation of new executable artifacts.
  • Suggested Filter/Exclusion: Exclude file paths starting with C:\Windows\CCMCache\ from the detection scope. Additionally, filter out events where the parent process is ccmexec.exe and the user context is NT AUTHORITY\SYSTEM.

• Scenario: Backup Solutions (Veeam or Commvault) Agent Operations

  • Context: Enterprise backup agents (e.g., Veeam Transport Service or Commvault MediaAgent) frequently bind to network resources to replicate data. The YARA rule might misinterpret the agent’s process spawning child processes for data transfer as a suspicious “naked” binding activity, particularly when accessing shared folders over