SpecialEXEPasswordProtectorv10

Hunt Hypothesis

This rule identifies the presence of the SpecialEXEPasswordProtector tool, a utility commonly used by adversaries to obfuscate executable files with password protection to evade static analysis and signature-based detection. Proactively hunting for this indicator in Azure Sentinel allows the SOC team to uncover hidden payloads or staged components that may be deployed during post-exploitation activities, ensuring timely identification of low-severity threats that could facilitate further compromise.

YARA Rule

rule SpecialEXEPasswordProtectorv10
{
      meta:
		author="malware-lu"
strings:
		$a0 = { 60 E8 00 00 00 00 5D 81 ED 06 00 00 00 89 AD 8C 01 00 00 8B C5 2B 85 FE 75 00 00 89 85 3E 77 }

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 specific false positive scenarios for the SpecialEXEPasswordProtectorv10 YARA rule, along with suggested filters:

• Legacy Application Deployment via SCCM/MECM: In many enterprise environments, older line-of-business applications (e.g., legacy ERP modules or specialized engineering tools) are distributed via System Center Configuration Manager (SCCM) or Microsoft Endpoint Configuration Manager (MECM). These packages often include a self-extracting archive or a password-protected installer wrapper (e.g., using 7-Zip SFX or WinRAR SFX) that matches the “PasswordProtector” signature.

  • Filter/Exclusion: Exclude processes where the parent process is ccmsetup.exe (SCCM client) or execagent.exe (MECM agent), or exclude files located in standard deployment directories like C:\Windows\CCM\ or C:\Program Files\Microsoft Configuration Manager\.

• Scheduled Backup Jobs with Encrypted Archives: Enterprise backup solutions (such as Veeam, Commvault, or Veritas) often create encrypted backup sets or use password-protected archive formats for off-site transfer. If a scheduled task (e.g., Task Scheduler job named “NightlyBackup”) executes a helper executable to manage these archives, the binary may match the YARA rule.

  • Filter/Exclusion: Exclude processes whose command line contains keywords like backup, archive, or encrypt, or exclude files located in known backup service directories (e.g., C:\Program Files\Veeam\, C:\Program Files\Commvault\). Additionally, exclude if the parent process is svchost.exe running a specific backup-related service.

• Password Manager Auto-Update Mechanisms: Enterprise password managers like 1Password, LastPass, or KeePass (especially when deployed via GPO or MDM) may