Detect Malicious Vbscript Base64

Daniel Jeremiah@daniyyell

•updated Jun 19, 2026•0•0•7

This rule detects malicious VBScript patterns, including Base64 decoding, file operations, and PowerShell execution. It looks for specific VBScript functions and object creations like `CreateObject("MSXML2.DOMDocument.3.0")`, `CreateObject("Scripting.FileSystemObject")`, and `CreateObject("Wscript.Shell")`, as well as patterns related to Base64 decoding. Additionally, it identifies common malicious PowerShell usage through keywords such as `powershell.exe -nop`, `-encodedcommand`, `Invoke-Expression`, `DownloadString`, and various execution policy bypasses or obfuscation techniques. The rule also includes patterns for VBScript window manipulation and script language declarations.