Sigma Rules
3,116 rules found for "sigma"
Uncommon File Created In Office Startup Folder
Detects the creation of a file with an uncommon extension in an Office application startup folder
PCRE.NET Package Temp Files
Detects processes creating temp files related to PCRE.NET package
Suspicious File Created In PerfLogs
Detects suspicious file based on their extension being created in "C:\PerfLogs\". Note that this directory mostly contains ".etl" files
Potential Binary Or Script Dropper Via PowerShell
Detects PowerShell creating a binary executable or a script file.
PowerShell Script Dropped Via PowerShell.EXE
Detects PowerShell creating a PowerShell file (.ps1). While often times this behavior is benign, sometimes it can be a sign of a dropper script trying to achieve persistence.
Malicious PowerShell Scripts - FileCreation
Detects the creation of known offensive powershell scripts used for exploitation
PowerShell Module File Created
Detects the creation of a new PowerShell module ".psm1", ".psd1", ".dll", ".ps1", etc.
Potential Suspicious PowerShell Module File Created
Detects the creation of a new PowerShell module in the first folder of the module directory structure "\WindowsPowerShell\Modules\malware\malware.psm1". This is somewhat an uncommon practice as legitimate modules often includes a version folder.
PowerShell Module File Created By Non-PowerShell Process
Detects the creation of a new PowerShell module ".psm1", ".psd1", ".dll", ".ps1", etc. by a non-PowerShell process
Potential Startup Shortcut Persistence Via PowerShell.EXE
Detects PowerShell writing startup shortcuts. This procedure was highlighted in Red Canary Intel Insights Oct. 2021, "We frequently observe adversaries using PowerShell to write malicious .lnk files into the startup directory to establish persistence. Accordingly, this detection opportunity is likely to identify persistence mechanisms in multiple threats. In the context of Yellow Cockatoo, this persistence mechanism eventually launches the command-line script that leads to the installation of a malicious DLL"
PSScriptPolicyTest Creation By Uncommon Process
Detects the creation of the "PSScriptPolicyTest" PowerShell script by an uncommon process. This file is usually generated by Microsoft Powershell to test against Applocker.
Rclone Config File Creation
Detects Rclone config files being created
.RDP File Created By Uncommon Application
Detects creation of a file with an ".rdp" extension by an application that doesn't commonly create such files.
Potential Winnti Dropper Activity
Detects files dropped by Winnti as described in RedMimicry Winnti playbook
PDF File Created By RegEdit.EXE
Detects the creation of a file with the ".pdf" extension by the "RegEdit.exe" process. This indicates that a user is trying to print/save a registry key as a PDF in order to potentially extract sensitive information and bypass defenses.
RemCom Service File Creation
Detects default RemCom service filename which indicates RemCom service installation and execution
ScreenConnect Temporary Installation Artefact
An adversary may use legitimate desktop support and remote access software, such as Team Viewer, Go2Assist, LogMein, AmmyyAdmin, etc, to establish an interactive command and control channel to target systems within networks. These services are commonly used as legitimate technical support software, and may be allowed by application control within a target environment. Remote access tools like VNC, Ammyy, and Teamviewer are used frequently when compared with other legitimate software commonly used by adversaries. (Citation: Symantec Living off the Land)
Remote Access Tool - ScreenConnect Temporary File
Detects the creation of files in a specific location by ScreenConnect RMM. ScreenConnect has feature to remotely execute binaries on a target machine. These binaries will be dropped to ":\Users\<username>\Documents\ConnectWiseControl\Temp\" before execution.
Potential RipZip Attack on Startup Folder
Detects a phishing attack which expands a ZIP file containing a malicious shortcut. If the victim expands the ZIP file via the explorer process, then the explorer process expands the malicious ZIP file and drops a malicious shortcut redirected to a backdoor into the Startup folder. Additionally, the file name of the malicious shortcut in Startup folder contains {0AFACED1-E828-11D1-9187-B532F1E9575D} meaning the folder shortcut operation.
Potential SAM Database Dump
Detects the creation of files that look like exports of the local SAM (Security Account Manager)
Self Extraction Directive File Created In Potentially Suspicious Location
Detects the creation of Self Extraction Directive files (.sed) in a potentially suspicious location. These files are used by the "iexpress.exe" utility in order to create self extracting packages. Attackers were seen abusing this utility and creating PE files with embedded ".sed" entries.
Windows Shell/Scripting Application File Write to Suspicious Folder
Detects Windows shells and scripting applications that write files to suspicious folders
Windows Binaries Write Suspicious Extensions
Detects Windows executables that write files with suspicious extensions
Startup Folder File Write
A General detection for files being created in the Windows startup directory. This could be an indicator of persistence.
Suspicious Creation with Colorcpl
Once executed, colorcpl.exe will copy the arbitrary file to c:\windows\system32\spool\drivers\color\
Created Files by Microsoft Sync Center
This rule detects suspicious files created by Microsoft Sync Center (mobsync)
Suspicious Files in Default GPO Folder
Detects the creation of copy of suspicious files (EXE/DLL) to the default GPO storage folder
Suspicious Creation TXT File in User Desktop
Ransomware create txt file in the user Desktop
Suspicious Desktopimgdownldr Target File
Detects a suspicious Microsoft desktopimgdownldr file creation that stores a file to a suspicious location or contains a file with a suspicious extension
Creation of a Diagcab
Detects the creation of diagcab file, which could be caused by some legitimate installer or is a sign of exploitation (review the filename and its location)
Suspicious Double Extension Files
Detects dropped files with double extensions, which is often used by malware as a method to abuse the fact that Windows hide default extensions by default.
DPAPI Backup Keys And Certificate Export Activity IOC
Detects file names with specific patterns seen generated and used by tools such as Mimikatz and DSInternals related to exported or stolen DPAPI backup keys and certificates.
Suspicious MSExchangeMailboxReplication ASPX Write
Detects suspicious activity in which the MSExchangeMailboxReplication process writes .asp and .apsx files to disk, which could be a sign of ProxyShell exploitation
Suspicious Executable File Creation
Detect creation of suspicious executable file names. Some strings look for suspicious file extensions, others look for filenames that exploit unquoted service paths.
Suspicious File Write to Webapps Root Directory
Detects suspicious file writes to the root directory of web applications, particularly Apache web servers or Tomcat servers. This may indicate an attempt to deploy malicious files such as web shells or other unauthorized scripts.
Suspicious File Write to SharePoint Layouts Directory
Detects suspicious file writes to SharePoint layouts directory which could indicate webshell activity or post-exploitation. This behavior has been observed in the exploitation of SharePoint vulnerabilities such as CVE-2025-49704, CVE-2025-49706 or CVE-2025-53770.
Suspicious Get-Variable.exe Creation
Get-Variable is a valid PowerShell cmdlet WindowsApps is by default in the path where PowerShell is executed. So when the Get-Variable command is issued on PowerShell execution, the system first looks for the Get-Variable executable in the path and executes the malicious binary instead of looking for the PowerShell cmdlet.
Potential Hidden Directory Creation Via NTFS INDEX_ALLOCATION Stream
Detects the creation of hidden file/folder with the "::$index_allocation" stream. Which can be used as a technique to prevent access to folder and files from tooling such as "explorer.exe" and "powershell.exe"
Potential Homoglyph Attack Using Lookalike Characters in Filename
Detects the presence of unicode characters which are homoglyphs, or identical in appearance, to ASCII letter characters. This is used as an obfuscation and masquerading techniques. Only "perfect" homoglyphs are included; these are characters that are indistinguishable from ASCII characters and thus may make excellent candidates for homoglyph attack characters.
Legitimate Application Dropped Archive
Detects programs on a Windows system that should not write an archive to disk
Legitimate Application Dropped Executable
Detects programs on a Windows system that should not write executables to disk
Legitimate Application Writing Files In Uncommon Location
Detects legitimate applications writing any type of file to uncommon or suspicious locations that are not typical for application data storage or execution. Adversaries may leverage legitimate applications (Living off the Land Binaries - LOLBins) to drop or download malicious files to uncommon locations on the system to evade detection by security solutions.
Legitimate Application Dropped Script
Detects programs on a Windows system that should not write scripts to disk
Suspicious LNK Double Extension File Created
Detects the creation of files with an "LNK" as a second extension. This is sometimes used by malware as a method to abuse the fact that Windows hides the "LNK" extension by default.
PowerShell Profile Modification
Detects the creation or modification of a powershell profile which could indicate suspicious activity as the profile can be used as a mean of persistence
Suspicious PROCEXP152.sys File Created In TMP
Detects the creation of the PROCEXP152.sys file in the application-data local temporary folder. This driver is used by Sysinternals Process Explorer but also by KDU (https://github.com/hfiref0x/KDU) or Ghost-In-The-Logs (https://github.com/bats3c/Ghost-In-The-Logs), which uses KDU.
Suspicious Binaries and Scripts in Public Folder
Detects the creation of a file with a suspicious extension in the public folder, which could indicate potential malicious activity.
Suspicious File Creation Activity From Fake Recycle.Bin Folder
Detects file write event from/to a fake recycle bin folder that is often used as a staging directory for malware