Sigma Rules
3,116 rules found
WinDivert Driver Load
Detects the load of the Windiver driver, a powerful user-mode capture/sniffing/modification/blocking/re-injection package for Windows
Credential Manager Access By Uncommon Applications
Detects suspicious processes based on name and location that access the windows credential manager and vault. Which can be a sign of credential stealing. Example case would be usage of mimikatz "dpapi::cred" function
Access To Windows Credential History File By Uncommon Applications
Detects file access requests to the Windows Credential History File by an uncommon application. This can be a sign of credential stealing. Example case would be usage of mimikatz "dpapi::credhist" function
Access To Crypto Currency Wallets By Uncommon Applications
Detects file access requests to crypto currency files by uncommon processes. Could indicate potential attempt of crypto currency wallet stealing.
Access To Windows DPAPI Master Keys By Uncommon Applications
Detects file access requests to the the Windows Data Protection API Master keys by an uncommon application. This can be a sign of credential stealing. Example case would be usage of mimikatz "dpapi::masterkey" function
Access To Potentially Sensitive Sysvol Files By Uncommon Applications
Detects file access requests to potentially sensitive files hosted on the Windows Sysvol share.
Suspicious File Access to Browser Credential Storage
Detects file access to browser credential storage paths by non-browser processes, which may indicate credential access attempts. Adversaries may attempt to access browser credential storage to extract sensitive information such as usernames and passwords or cookies. This behavior is often commonly observed in credential stealing malware.
Microsoft Teams Sensitive File Access By Uncommon Applications
Detects file access attempts to sensitive Microsoft teams files (leveldb, cookies) by an uncommon process.
Unusual File Modification by dns.exe
Detects an unexpected file being modified by dns.exe which my indicate activity related to remote code execution or other forms of exploitation as seen in CVE-2020-1350 (SigRed)
Backup Files Deleted
Detects deletion of files with extensions often used for backup files. Adversaries may delete or remove built-in operating system data and turn off services designed to aid in the recovery of a corrupted system to prevent recovery.
EventLog EVTX File Deleted
Detects the deletion of the event log files which may indicate an attempt to destroy forensic evidence
Exchange PowerShell Cmdlet History Deleted
Detects the deletion of the Exchange PowerShell cmdlet History logs which may indicate an attempt to destroy forensic evidence
IIS WebServer Access Logs Deleted
Detects the deletion of IIS WebServer access logs which may indicate an attempt to destroy forensic evidence
Process Deletion of Its Own Executable
Detects the deletion of a process's executable by itself. This is usually not possible without workarounds and may be used by malware to hide its traces.
PowerShell Console History Logs Deleted
Detects the deletion of the PowerShell console History logs which may indicate an attempt to destroy forensic evidence
Prefetch File Deleted
Detects the deletion of a prefetch file which may indicate an attempt to destroy forensic evidence
TeamViewer Log File Deleted
Detects the deletion of the TeamViewer log files which may indicate an attempt to destroy forensic evidence
Tomcat WebServer Logs Deleted
Detects the deletion of tomcat WebServer logs which may indicate an attempt to destroy forensic evidence
File Deleted Via Sysinternals SDelete
Detects the deletion of files by the Sysinternals SDelete utility. It looks for the common name pattern used to rename files.
Unusual File Deletion by Dns.exe
Detects an unexpected file being deleted by dns.exe which my indicate activity related to remote code execution or other forms of exploitation as seen in CVE-2020-1350 (SigRed)
ADS Zone.Identifier Deleted By Uncommon Application
Detects the deletion of the "Zone.Identifier" ADS by an uncommon process. Attackers can leverage this in order to bypass security restrictions that make use of the ADS such as Microsoft Office apps.
ADSI-Cache File Creation By Uncommon Tool
Detects the creation of an "Active Directory Schema Cache File" (.sch) file by an uncommon tool.
Advanced IP Scanner - File Event
Detects the use of Advanced IP Scanner. Seems to be a popular tool for ransomware groups.
Anydesk Temporary 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)
Suspicious Binary Writes Via AnyDesk
Detects AnyDesk writing binary files to disk other than "gcapi.dll". According to RedCanary research it is highly abnormal for AnyDesk to write executable files to disk besides gcapi.dll, which is a legitimate DLL that is part of the Google Chrome web browser used to interact with the Google Cloud API. (See reference section for more details)
Suspicious File Created by ArcSOC.exe
Detects instances where the ArcGIS Server process ArcSOC.exe, which hosts REST services running on an ArcGIS server, creates a file with suspicious file type, indicating that it may be an executable, script file, or otherwise unusual.
Assembly DLL Creation Via AspNetCompiler
Detects the creation of new DLL assembly files by "aspnet_compiler.exe", which could be a sign of "aspnet_compiler" abuse to proxy execution through a build provider.
BloodHound Collection Files
Detects default file names outputted by the BloodHound collection tool SharpHound
Potentially Suspicious File Creation by OpenEDR's ITSMService
Detects the creation of potentially suspicious files by OpenEDR's ITSMService process. The ITSMService is responsible for remote management operations and can create files on the system through the Process Explorer or file management features. While legitimate for IT operations, creation of executable or script files could indicate unauthorized file uploads, data staging, or malicious file deployment.
EVTX Created In Uncommon Location
Detects the creation of new files with the ".evtx" extension in non-common or non-standard location. This could indicate tampering with default EVTX locations in order to evade security controls or simply exfiltration of event log to search for sensitive information within. Note that backup software and legitimate administrator might perform similar actions during troubleshooting.
Creation Of Non-Existent System DLL
Detects creation of specific system DLL files that are usually not present on the system (or at least not in system directories) but may be loaded by legitimate processes. Phantom DLL hijacking involves placing malicious DLLs with names of non-existent system binaries in locations where legitimate applications may search for them, leading to execution of the malicious DLLs. Thus, the creation of such DLLs may indicate preparation for phantom DLL hijacking attacks.
Suspicious Deno File Written from Remote Source
Detects Deno writing a file from a direct HTTP(s) call and writing to the appdata folder or bringing it's own malicious DLL. This behavior may indicate an attempt to execute remotely hosted, potentially malicious files through deno.
New Custom Shim Database Created
Adversaries may establish persistence and/or elevate privileges by executing malicious content triggered by application shims. The Microsoft Windows Application Compatibility Infrastructure/Framework (Application Shim) was created to allow for backward compatibility of software as the operating system codebase changes over time.
Suspicious Screensaver Binary File Creation
Adversaries may establish persistence by executing malicious content triggered by user inactivity. Screensavers are programs that execute after a configurable time of user inactivity and consist of Portable Executable (PE) files with a .scr file extension
Files With System DLL Name In Unsuspected Locations
Detects the creation of a file with the ".dll" extension that has the name of a System DLL in uncommon or unsuspected locations. (Outisde of "System32", "SysWOW64", etc.). It is highly recommended to perform an initial baseline before using this rule in production.
Files With System Process Name In Unsuspected Locations
Detects the creation of an executable with a system process name in folders other than the system ones (System32, SysWOW64, etc.). It is highly recommended to perform an initial baseline before using this rule in production.
Creation Exe for Service with Unquoted Path
Adversaries may execute their own malicious payloads by hijacking vulnerable file path references. Adversaries can take advantage of paths that lack surrounding quotations by placing an executable in a higher level directory within the path, so that Windows will choose the adversary's executable to launch.
Cred Dump Tools Dropped Files
Files with well-known filenames (parts of credential dump software or files produced by them) creation
WScript or CScript Dropper - File
Detects a file ending in jse, vbe, js, vba, vbs written by cscript.exe or wscript.exe
CSExec Service File Creation
Detects default CSExec service filename which indicates CSExec service installation and execution
Dynamic CSharp Compile Artefact
When C# is compiled dynamically, a .cmdline file will be created as a part of the process. Certain processes are not typically observed compiling C# code, but can do so without touching disk. This can be used to unpack a payload for execution
Potential DCOM InternetExplorer.Application DLL Hijack
Detects potential DLL hijack of "iertutil.dll" found in the DCOM InternetExplorer.Application Class over the network
Desktop.INI Created by Uncommon Process
Detects unusual processes accessing desktop.ini, which can be leveraged to alter how Explorer displays a folder's content (i.e. renaming files) without changing them on disk.
DLL Search Order Hijackig Via Additional Space in Path
Detects when an attacker create a similar folder structure to windows system folders such as (Windows, Program Files...) but with a space in order to trick DLL load search order and perform a "DLL Search Order Hijacking" attack
Potentially Suspicious DMP/HDMP File Creation
Detects the creation of a file with the ".dmp"/".hdmp" extension by a shell or scripting application such as "cmd", "powershell", etc. Often created by software during a crash. Memory dumps can sometimes contain sensitive information such as credentials. It's best to determine the source of the crash.
Potential Persistence Attempt Via ErrorHandler.Cmd
Detects creation of a file named "ErrorHandler.cmd" in the "C:\WINDOWS\Setup\Scripts\" directory which could be used as a method of persistence The content of C:\WINDOWS\Setup\Scripts\ErrorHandler.cmd is read whenever some tools under C:\WINDOWS\System32\oobe\ (e.g. Setup.exe) fail to run for any reason.
Suspicious ASPX File Drop by Exchange
Detects suspicious file type dropped by an Exchange component in IIS into a suspicious folder
Suspicious File Drop by Exchange
Detects suspicious file type dropped by an Exchange component in IIS