Sigma Rules
294 rules found
Suspicious Uninstall of Windows Defender Feature via PowerShell
Detects the use of PowerShell with Uninstall-WindowsFeature or Remove-WindowsFeature cmdlets to disable or remove the Windows Defender GUI feature, a common technique used by adversaries to evade defenses.
PUA - AdFind.EXE Execution
Detects execution of Adfind.exe utility, which can be used for reconnaissance in an Active Directory environment
PUA - Kernel Driver Utility (KDU) Execution
Detects execution of the Kernel Driver Utility (KDU) tool. KDU can be used to bypass driver signature enforcement and load unsigned or malicious drivers into the Windows kernel. Potentially allowing for privilege escalation, persistence, or evasion of security controls.
PUA - Memory Dump Mount Via MemProcFS
Detects execution of MemProcFS a memory forensics tool with the '-device' parameter. MemProcFS mounts physical memory as a virtual file system, allowing direct access to process memory and system structures. Threat actors were seen abusing this utility to mount memory dumps and then extract sensitive information from processes like LSASS or extract registry hives to obtain credentials, LSA secrets, SAM data, and cached domain credentials. MemProcFS usage that is not part of authorized forensic analysis should be treated as suspicious and warrants further investigation.
PUA - Restic Backup Tool Execution
Detects the execution of the Restic backup tool, which can be used for data exfiltration. Threat actors may leverage Restic to back up and exfiltrate sensitive data to remote storage locations, including cloud services. If not legitimately used in the enterprise environment, its presence may indicate malicious activity.
PUA - TruffleHog Execution
Detects execution of TruffleHog, a tool used to search for secrets in different platforms like Git, Jira, Slack, SharePoint, etc. that could be used maliciously. While it is a legitimate tool, intended for use in CI pipelines and security assessments, It was observed in the Shai-Hulud malware campaign targeting npm packages to steal sensitive information.
Python One-Liners with Base64 Decoding
Detects Python one-liners that use base64 decoding functions in command line executions. Malicious scripts or attackers often use python one-liners to decode and execute base64-encoded payloads, which is a common technique for obfuscation and evasion.
QuickAssist Execution
Detects the execution of Microsoft Quick Assist tool "QuickAssist.exe". This utility can be used by attackers to gain remote access.
RDP Enable or Disable via Win32_TerminalServiceSetting WMI Class
Detects enabling or disabling of Remote Desktop Protocol (RDP) using alternate methods such as WMIC or PowerShell. In PowerShell one-liner commands, the "SetAllowTSConnections" method of the "Win32_TerminalServiceSetting" class may be used to enable or disable RDP. In WMIC, the "rdtoggle" alias or "Win32_TerminalServiceSetting" class may be used for the same purpose.
Windows Recovery Environment Disabled Via Reagentc
Detects attempts to disable windows recovery environment using Reagentc. ReAgentc.exe is a command-line tool in Windows used to manage the Windows Recovery Environment (WinRE). It allows users to enable, disable, and configure WinRE, which is used for troubleshooting and repairing common boot issues.
RegAsm.EXE Execution Without CommandLine Flags or Files
Detects the execution of "RegAsm.exe" without a commandline flag or file, which might indicate potential process injection activity. Usually "RegAsm.exe" should point to a dedicated DLL file or call the help with the "/?" flag.
Registry Export of Third-Party Credentials
Detects the use of reg.exe to export registry paths associated with third-party credentials. Credential stealers have been known to use this technique to extract sensitive information from the registry.
RunMRU Registry Key Deletion
Detects deletion of the RunMRU registry key, which stores the history of commands executed via the Run dialog. In the clickfix techniques, the phishing lures instruct users to open a run dialog through (Win + R) and execute malicious commands. Adversaries may delete this key to cover their tracks after executing commands.
Disabling Windows Defender WMI Autologger Session via Reg.exe
Detects the use of reg.exe to disable the Event Tracing for Windows (ETW) Autologger session for Windows Defender API and Audit events. By setting the 'Start' value to '0' for the 'DefenderApiLogger' or 'DefenderAuditLogger' session, an attacker can prevent these critical security events from being logged, effectively blinding monitoring tools that rely on this data. This is a powerful defense evasion technique.
System Language Discovery via Reg.Exe
Detects the usage of Reg.Exe to query system language settings. Attackers may discover the system language to determine the geographic location of victims, customize payloads for specific regions, or avoid targeting certain locales to evade detection.
System Restore Registry Modification via CommandLine
Detects system restore registry modification via command line, which can be used by adversaries to disable system restore on the computer.
Remote Access Tool - Potential MeshAgent Execution - Windows
Detects potential execution of MeshAgent which is a tool used for remote access. Historical data shows that threat actors rename MeshAgent binary to evade detection. Matching command lines with the '--meshServiceName' argument can indicate that the MeshAgent is being used for remote access.
Remote Access Tool - Renamed MeshAgent Execution - Windows
Detects the execution of a renamed instance of the Remote Monitoring and Management (RMM) tool, MeshAgent. RMM tools such as MeshAgent are commonly utilized by IT administrators for legitimate remote support and system management. However, malicious actors may exploit these tools by renaming them to bypass detection mechanisms, enabling unauthorized access and control over compromised systems.
Remote Access Tool - TacticalRMM Agent Registration to Potentially Attacker-Controlled Server
Detects TacticalRMM agent installations where the --api, --auth, and related flags are used on the command line. These parameters configure the agent to connect to a specific RMM server with authentication, client ID, and site ID. This technique could indicate a threat actor attempting to register the agent with an attacker-controlled RMM infrastructure silently.
Renamed Schtasks Execution
Detects the execution of renamed schtasks.exe binary, which is a legitimate Windows utility used for scheduling tasks. One of the very common persistence techniques is schedule malicious tasks using schtasks.exe. Since, it is heavily abused, it is also heavily monitored by security products. To evade detection, threat actors may rename the schtasks.exe binary to schedule their malicious tasks.
Scheduled Task Creation with Curl and PowerShell Execution Combo
Detects the creation of a scheduled task using schtasks.exe, potentially in combination with curl for downloading payloads and PowerShell for executing them. This facilitates executing malicious payloads or connecting with C&C server persistently without dropping the malware sample on the host.
Potential SSH Tunnel Persistence Install Using A Scheduled Task
Detects the creation of new scheduled tasks via commandline, using Schtasks.exe. This rule detects tasks creating that call OpenSSH, which may indicate the creation of reverse SSH tunnel to the attacker's server.
Scheduled Task Creation Masquerading as System Processes
Detects the creation of scheduled tasks that involve system processes, which may indicate malicious actors masquerading as or abusing these processes to execute payloads or maintain persistence.
NodeJS Execution of JavaScript File
Detects execution of JavaScript or JSC files using NodeJs binary node.exe, that could be potentially suspicious. Node.js is a popular open-source JavaScript runtime that runs code outside browsers and is widely used for both frontend and backend development. Adversaries have been observed abusing Node.js to disguise malware as legitimate processes, evade security defenses, and maintain persistence within target systems. Because Node.js is commonly used, this rule may generate false positives in some environments. However, if such activity is unusual in your environment, it is highly suspicious and warrants immediate investigation.
Indirect Command Execution via SFTP ProxyCommand
Detects the use of SFTP.exe to execute commands indirectly via ProxyCommand parameter. Threat actors were seen leveraging this legitimate Windows binary to bypass security controls and execute arbitrary commands while evading detection.
Suspicious Speech Runtime Binary Child Process
Detects suspicious Speech Runtime Binary Execution by monitoring its child processes. Child processes spawned by SpeechRuntime.exe could indicate an attempt for lateral movement via COM & DCOM hijacking.
Suspicious ClickFix/FileFix Execution Pattern
Detects suspicious execution patterns where users are tricked into running malicious commands via clipboard manipulation, either through the Windows Run dialog (ClickFix) or File Explorer address bar (FileFix). Attackers leverage social engineering campaigns—such as fake CAPTCHA challenges or urgent alerts—encouraging victims to paste clipboard contents, often executing mshta.exe, powershell.exe, or similar commands to infect systems.
Suspicious Explorer Process with Whitespace Padding - ClickFix/FileFix
Detects process creation with suspicious whitespace padding followed by a '#' character, which may indicate ClickFix or FileFix techniques used to conceal malicious commands from visual inspection. ClickFix and FileFix are social engineering attack techniques where adversaries distribute phishing documents or malicious links that deceive users into opening the Windows Run dialog box or File Explorer search bar. The victims are then instructed to paste commands from their clipboard, which contain extensive whitespace padding using various Unicode space characters to push the actual malicious command far to the right, effectively hiding it from immediate view.
Suspicious Usage of For Loop with Recursive Directory Search in CMD
Detects suspicious usage of the cmd.exe 'for /f' loop combined with the 'tokens=' parameter and a recursive directory listing. This pattern may indicate an attempt to discover and execute system binaries dynamically, for example powershell, a technique sometimes used by attackers to evade detection. This behavior has been observed in various malicious lnk files.
Suspicious FileFix Execution Pattern
Detects suspicious FileFix execution patterns where users are tricked into running malicious commands through browser file upload dialog manipulation. This attack typically begins when users visit malicious websites impersonating legitimate services or news platforms, which may display fake CAPTCHA challenges or direct instructions to open file explorer and paste clipboard content. The clipboard content usually contains commands that download and execute malware, such as information stealing tools.
Potentially Suspicious Inline JavaScript Execution via NodeJS Binary
Detects potentially suspicious inline JavaScript execution using Node.js with specific keywords in the command line.
Suspicious LNK Command-Line Padding with Whitespace Characters
Detects exploitation of LNK file command-line length discrepancy, where attackers hide malicious commands beyond the 260-character UI limit while the actual command-line argument field supports 4096 characters using whitespace padding (e.g., 0x20, 0x09-0x0D). Adversaries insert non-printable whitespace characters (e.g., Line Feed \x0A, Carriage Return \x0D) to pad the visible section of the LNK file, pushing malicious commands past the UI-visible boundary. The hidden payload, executed at runtime but invisible in Windows Explorer properties, enables stealthy execution and evasion—commonly used for social engineering attacks. This rule flags suspicious use of such padding observed in real-world attacks.
Script Interpreter Spawning Credential Scanner - Windows
Detects a script interpreter process (like node.js or bun) spawning a known credential scanning tool (e.g., trufflehog, gitleaks). This behavior is indicative of an attempt to find and steal secrets, as seen in the "Shai-Hulud: The Second Coming" campaign.
Suspicious Velociraptor Child Process
Detects the suspicious use of the Velociraptor DFIR tool to execute other tools or download additional payloads, as seen in a campaign where it was abused for remote access and to stage further attacks.
Uncommon Svchost Command Line Parameter
Detects instances of svchost.exe running with an unusual or uncommon command line parameter by excluding known legitimate or common patterns. This could point at a file masquerading as svchost, a process injection, or hollowing of a legitimate svchost instance.
User Shell Folders Registry Modification via CommandLine
Detects modifications to User Shell Folders registry values via reg.exe or PowerShell, which could indicate persistence attempts. Attackers may modify User Shell Folders registry values to point to malicious executables or scripts that will be executed during startup. This technique is often used to maintain persistence on a compromised system by ensuring that malicious payloads are executed automatically.
Registry Modification Attempt Via VBScript
Detects attempts to modify the registry using VBScript's CreateObject("Wscript.shell") and RegWrite methods via common LOLBINs. It could be an attempt to modify the registry for persistence without using straightforward methods like regedit.exe, reg.exe, or PowerShell. Threat Actors may use this technique to evade detection by security solutions that monitor for direct registry modifications through traditional tools.
Proxy Execution via Vshadow
Detects the invocation of vshadow.exe with the -exec parameter that executes a specified script or command after the shadow copies are created but before the VShadow tool exits. VShadow is a command-line tool that you can use to create and manage volume shadow copies. While legitimate backup or administrative scripts may use this flag, attackers can leverage this parameter to proxy the execution of malware.
Vulnerable Driver Blocklist Registry Tampering Via CommandLine
Detects tampering of the Vulnerable Driver Blocklist registry via command line tools such as PowerShell or REG.EXE. The Vulnerable Driver Blocklist is a security feature that helps prevent the loading of known vulnerable drivers. Disabling this feature may indicate an attempt to bypass security controls, often targeted by threat actors to facilitate the installation of malicious or vulnerable drivers, particularly in scenarios involving Endpoint Detection and Response
PPL Tampering Via WerFaultSecure
Detects potential abuse of WerFaultSecure.exe to dump Protected Process Light (PPL) processes like LSASS or to freeze security solutions (EDR/antivirus). This technique is used by tools such as EDR-Freeze and WSASS to bypass PPL protections and access sensitive information or disable security software. Distinct command line patterns help identify the specific tool: - WSASS usage typically shows: "WSASS.exe WerFaultSecure.exe [PID]" in ParentCommandLine - EDR-Freeze usage typically shows: "EDR-Freeze_[version].exe [PID] [timeout]" in ParentCommandLine Legitimate debugging operations using WerFaultSecure are rare in production environments and should be investigated.
Potential Lateral Movement via Windows Remote Shell
Detects a child process spawned by 'winrshost.exe', which suggests remote command execution through Windows Remote Shell (WinRs) and may indicate potential lateral movement activity.
Winrs Local Command Execution
Detects the execution of Winrs.exe where it is used to execute commands locally. Commands executed this way are launched under Winrshost.exe and can represent proxy execution used for defense evasion or lateral movement.
Wlrmdr.EXE Uncommon Argument Or Child Process
Detects the execution of "Wlrmdr.exe" with the "-u" command line flag which allows anything passed to it to be an argument of the ShellExecute API, which would allow an attacker to execute arbitrary binaries. This detection also focuses on any uncommon child processes spawned from "Wlrmdr.exe" as a supplement for those that posses "ParentImage" telemetry.
Service Startup Type Change Via Wmic.EXE
Detects changes to service startup type to 'disabled' or 'manual' using the WMIC command-line utility.
Registry Manipulation via WMI Stdregprov
Detects the usage of wmic.exe to manipulate Windows registry via the WMI StdRegProv class. This behaviour could be potentially suspicious because it uses an alternative method to modify registry keys instead of legitimate registry tools like reg.exe or regedit.exe. Attackers specifically choose this technique to evade detection and bypass security monitoring focused on traditional registry modification commands.
Password Set to Never Expire via WMI
Detects the use of wmic.exe to modify user account settings and explicitly disable password expiration.
Installation of WSL Kali-Linux
Detects installation of Kali Linux distribution through Windows Subsystem for Linux (WSL). Attackers may use Kali Linux WSL to leverage its penetration testing tools and capabilities for malicious purposes.
WSL Kali-Linux Usage
Detects the use of Kali Linux through Windows Subsystem for Linux