Sigma detection rules, expert-reviewed

PowerShell Base64 Encoded MpPreference Command Lines for Windows Defender Modification

Detects PowerShell Base64 command lines referencing Add-MpPreference/Set-MpPreference to modify Microsoft Defender AV settings.

Windows Hacktool Execution Flagged by Imphash in Process Creation

Alerts on Windows process executions where the import hash matches known hacktool binaries, even if renamed.

Windows PowerShell: Disable Microsoft Defender Scanning via Set-MpPreference

Flags PowerShell commands that disable Microsoft Defender scanning/protection settings using Set-MpPreference, including encoded variants.

Windows: fsutil SymlinkEvaluation behavior modification via command line

Alerts on fsutil commands from cmd/PowerShell that change NTFS SymlinkEvaluation behavior, potentially enabling remote symlink access.

Windows Process Creation: Base64-Obfuscated .NET Reflection Assembly Load Call

Alerts on command lines containing Base64-encoded obfuscation for .NET reflection assembly load calls.

Windows PowerShell: Base64 Encoded Reflective .NET Assembly Load

Flags PowerShell command lines containing Base64 fragments consistent with reflective .NET Assembly.Load usage.

Windows BITS Transfer Jobs Downloading Files with Suspicious Extensions

Flags Windows BITS transfers saving local files with high-risk script/executable extensions while excluding common benign patterns.

Windows BITS Job Creation Triggered by PowerShell

Flags new BITS job creation on Windows when initiated by PowerShell (Event ID 3).

Windows BITS job created by bitsadmin.exe (BITS Client EventID 3)

Alerts on new BITS job creation when bitsadmin.exe triggers it (BITS-Client EventID 3).

Windows PowerShell CommandLine downloads and executes via WebClient with IEX or DownloadFile

Alerts on PowerShell command lines that use WebClient downloads combined with IEX or DownloadFile, typical of staged payload execution.

Windows: Suspicious Process Spawn by Outlook Parent

Alerts on Windows process launches where Outlook.exe spawns known high-risk command execution binaries.

Windows Registry: Enable Microsoft DDE in Word or Excel Security Settings

Detects registry changes that enable or permit DDE server launch/lookup for Word or Excel.

Suspicious wuauclt.exe Process Creation on Windows with Empty Command-Line Flags

Alert on Windows Update Agent wuauclt.exe launches that have command lines ending with no flags/arguments.

Windows: Suspicious Parent Process Execution From \Users\Public Spawning Scripting/Shell Binaries

Alerts on processes launched from \Users\Public that execute common scripting/shell binaries or command-line markers.

Windows: ScreenConnect Client Service Spawning Suspicious Utility Commands

Alerts when ScreenConnect run.cmd leads to child processes like cmd.exe, PowerShell, curl, or other utilities.