ASProtect 130824 beta

Hunt Hypothesis

This hypothesis targets the presence of ASProtect 130824 beta, a legacy commercial packer frequently abused by threat actors to obfuscate malicious payloads and evade static analysis. Proactively hunting for this specific version in Azure Sentinel allows the SOC to identify potentially compromised workloads or dormant backdoors that may have been introduced through older software bundles or supply chain attacks.

YARA Rule

rule ASProtect_130824_beta: PEiD
{
    strings:
        $a = { 68 01 ?? 40 00 E8 01 00 00 00 C3 C3 ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? 89 }
    condition:
        $a 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

• Legacy Financial Reporting Tool Execution: A specialized, internally developed financial reporting application (e.g., FinReport.exe) that has not been updated in several years may still be packed with an older version of ASProtect (build 130824) to protect intellectual property. This binary is executed by a service account via a scheduled task named Monthly_Financial_Close on the Finance Server.

  • Filter/Exclusion: Exclude files located in the C:\Apps\FinReport\bin\ directory or exclude the specific process name FinReport.exe if the file hash matches the known legacy build.

• Older Version of WinRAR or 7-Zip Installer: An IT department member manually runs an older, standalone installer for WinRAR (e.g., version 5.x or early 6.x) or a specific build of 7-Zip that was packed with ASProtect 130824 beta during its development cycle. This is often done to install software on a jump host or a server where the standard MSI installer is not supported.

  • Filter/Exclusion: Exclude processes named WinRAR.exe or 7z.exe when the parent process is explorer.exe or cmd.exe and the file path is under C:\Temp\ or C:\Users\<Admin>\Downloads\.

• Legacy Java Application Server Plugin: A critical legacy application server (e.g., an older version of WebLogic or Tomcat) loads a native plugin or helper library (e.g., jnidispatch.dll or a custom legacy_plugin.dll) that was compiled and packed with ASProtect 130824 beta. This DLL is loaded by the Java process (java.exe) during the daily batch processing job scheduled at 2:00 AM.

  • Filter/Exclusion: