Sigma Rules
2,839 rules found
Potential SharePoint ToolShell CVE-2025-53770 Exploitation - File Create
Detects the creation of file such as spinstall0.aspx which may indicate successful exploitation of CVE-2025-53770. CVE-2025-53770 is a zero-day vulnerability in SharePoint that allows remote code execution.
Potential SharePoint ToolShell CVE-2025-53770 Exploitation Indicators
Detects potential exploitation of CVE-2025-53770 by identifying indicators such as suspicious command lines discovered in Post-Exploitation activities. CVE-2025-53770 is a zero-day vulnerability in SharePoint that allows remote code execution.
Potential Exploitation of CrushFTP RCE Vulnerability (CVE-2025-54309)
Detects suspicious child processes created by CrushFTP. It could be an indication of exploitation of a RCE vulnerability such as CVE-2025-54309.
Windows Suspicious Child Process from Node.js - React2Shell
Detects suspicious child processes started by Node.js server processes on Windows, which may indicate exploitation of vulnerabilities like CVE-2025-55182 (React2Shell). Attackers can abuse the Node.js 'child_process' module to run system commands or scripts using methods such as spawn(), exec(), execFile(), fork(), or execSync(). If execSync() or exec() is used in the exploit, the command line often shows a shell (e.g., cmd.exe /d /s /c ...) running a suspicious command unless other shells are explicitly invoked. For other methods, the spawned process appears directly in the Image field unless a shell is explicitly used.
Commvault QLogin with PublicSharingUser and GUID Password (CVE-2025-57788)
Detects a qlogin.exe command attempting to authenticate as the internal `_+_PublicSharingUser_` using a GUID as the password. This could be an indicator of an attacker exploiting CVE-2025-57788 to gain initial access using leaked credentials.
Commvault QOperation Path Traversal Webshell Drop (CVE-2025-57790)
Detects the use of qoperation.exe with the -file argument to write a JSP file to the webroot, indicating a webshell drop. This is a post-authentication step corresponding to CVE-2025-57790.
Commvault QLogin Argument Injection Authentication Bypass (CVE-2025-57791)
Detects the use of argument injection in the Commvault qlogin command - potential exploitation for CVE-2025-57791. An attacker can inject the `-localadmin` parameter via the password field to bypass authentication and gain a privileged token.
Exploitation Activity of CVE-2025-59287 - WSUS Suspicious Child Process
Detects the creation of command-line interpreters (cmd.exe, powershell.exe) as child processes of Windows Server Update Services (WSUS) related process wsusservice.exe. This behavior is a key indicator of exploitation for the critical remote code execution vulnerability such as CVE-2025-59287, where attackers spawn shells to conduct reconnaissance and further post-exploitation activities.
Exploitation Activity of CVE-2025-59287 - WSUS Deserialization
Detects cast exceptions in Windows Server Update Services (WSUS) application logs that highly indicate exploitation attempts of CVE-2025-59287, a deserialization vulnerability in WSUS.
FunkLocker Ransomware File Creation
Detects the creation of files with the ".funksec" extension, which is appended to encrypted files by the FunkLocker ransomware.
Grixba Malware Reconnaissance Activity
Detects execution of the Grixba reconnaissance tool based on suspicious command-line parameter combinations. This tool is used by the Play ransomware group for network enumeration, data gathering, and event log clearing.
DNS Query To Katz Stealer Domains
Detects DNS queries to domains associated with Katz Stealer malware. Katz Stealer is a malware variant that is known to be used for stealing sensitive information from compromised systems. In Enterprise environments, DNS queries to these domains may indicate potential malicious activity or compromise.
Katz Stealer DLL Loaded
Detects loading of DLLs associated with Katz Stealer malware 2025 variants. Katz Stealer is a malware variant that is known to be used for stealing sensitive information from compromised systems. The process that loads these DLLs are very likely to be malicious.
Kalambur Backdoor Curl TOR SOCKS Proxy Execution
Detects the execution of the "curl.exe" command, referencing "SOCKS" and ".onion" domains, which could be indicative of Kalambur backdoor activity.
Shai-Hulud Malware Indicators - Windows
Detects potential Shai-Hulud malware indicators based on specific command line arguments associated with its execution.
Shai-Hulud Malicious Bun Execution
Detects the execution of `bun_environment.js` via the Bun runtime, a behavior associated with the Shai-Hulud "Second Coming" NPM supply chain attack. The malware uses a `setup_bun.js` script to install the Bun runtime if not present, and then executes the malicious `bun_environment.js` payload.
Shai-Hulud 2.0 Malicious NPM Package Installation
Detects the command-line installation of specific malicious npm packages and versions associated with the Shai-Hulud 2.0 supply chain attack.
Potential CVE-2026-33829 Exploitation - Windows Snipping Tool Remote File Path URI
Detects potential exploitation of CVE-2026-33829, a vulnerability in the Windows Snipping Tool URI handler (ms-screensketch:). An attacker can abuse the 'filePath' parameter to supply a UNC path or HTTP URL, causing SnippingTool.exe to initiate a connection to a remote resource. When a UNC path is used (e.g. \\attacker.com\share), this triggers an outbound NTLM authentication attempt, allowing the attacker to capture or relay the victim's Net-NTLMv2 hash. HTTP-based paths may result in remote file loading or server-side request forgery (SSRF)-style access. The URI can be delivered via a malicious hyperlink, phishing email, or web page.
RedSun - TieringEngineService.exe Staged in RS-Prefixed Temp Dir
Detects the creation of a file named TieringEngineService.exe inside a directory whose path contains the RS- prefix characteristic of RedSun's staging directory (e.g. %TEMP%\RS-{GUID}\TieringEngineService.exe). RedSun registers a Cloud Files sync root under this RS-prefixed path and drops a masqueraded placeholder there as part of its oplock-based AV bypass and privilege escalation chain. The RS-{GUID} directory name is generated by RedSun itself and has no legitimate system usage, making the combination of this path prefix and the TieringEngineService.exe filename a highly specific indicator of RedSun activity.
RedSun - Named Pipe Created
Detects the creation of a named pipe with the hardcoded name "REDSUN". The RedSun exploit tool uses a pipe with this name for synchronisation and command communication between its components during the Cloud Files API + oplock-based AV bypass and privilege escalation chain. RedSun creates the pipe as \\??\pipe\REDSUN. The pipe server listens for the token-duplicated elevated process to connect and respond, completing the privilege escalation from user to SYSTEM. Presence of this pipe name indicates active or recent RedSun execution.
RedSun - Conhost.exe Spawned by TieringEngineService.exe
Detects two stages of the RedSun post-exploitation process chain that deliver a SYSTEM-level shell to the attacker's interactive session. Observed process chain services.exe → TieringEngineService.exe → conhost.exe (SYSTEM, CommandLine: bare path, no arguments) → cmd.exe / shell (SYSTEM, TerminalSessionId = attacker's session) Stage 1 — TieringEngineService.exe spawns argument-less conhost.exe: After winning the oplock + Cloud Files mount point race, the malicious TieringEngineService.exe (RedSun.exe copied to System32, started via CoCreateInstance / services.exe) detects it is NT AUTHORITY\SYSTEM and calls LaunchConsoleInSessionId(). This opens \\.\pipe\REDSUN, reads the attacker's session ID, duplicates the SYSTEM token, re-stamps it with that session ID via SetTokenInformation(TokenSessionId), then calls CreateProcessAsUser to spawn conhost.exe with no arguments. Stage 2 — Shell spawned from rogue conhost.exe (EDR sources with GrandParentImage): The rogue SYSTEM conhost.exe spawns a shell (cmd.exe, PowerShell, etc.) as SYSTEM in the attacker's interactive session. On EDR sources that expose GrandParentImage, the full three-level chain (TieringEngineService.exe → conhost.exe → shell) can be matched directly. The legitimate TieringEngineService.exe is a headless COM server that is unlikely to spawn conhost.exe under normal conditions.
RedSun - TieringEngineService.exe Detected as EICAR Test File
Detects Windows Defender (EventID 1119 - Remediation Action Failed) flagging TieringEngineService.exe dropped in a characteristic RS-{GUID} temporary directory, or the RedSun.exe process itself being present. This covers the staging pattern used by RedSun, a Cloud Files API and opportunistic lock (oplock) based AV bypass/privilege escalation tool. RedSun works as follows: 1. Registers a Cloud Files sync root and creates a Cloud Files placeholder for TieringEngineService.exe under %TEMP%\RS-{GUID}\ 2. The placeholder file carries EICAR test file content (Virus:DOS/EICAR_Test_File) to reliably trigger a Defender scan and remediation attempt 3. Requests a batch oplock (FSCTL_REQUEST_BATCH_OPLOCK) on the placeholder file 4. When Defender attempts to scan/quarantine the file, the oplock triggers - holding the file open 5. During the oplock break window, RedSun swaps the mount point (junction) to redirect \\?\C:\Windows\System32 to the attacker-controlled temp path 6. This races the AV/OS into executing the malicious TieringEngineService.exe with elevated privileges
Axios NPM Compromise File Creation Indicators - Windows
Detects file creation events linked to the Axios NPM supply chain compromise. Axios is a popular JavaScript HTTP client. On March 30, 2026, malicious versions (1.14.1, 0.30.4) were published to npm, injecting a dependency (plain-crypto-js@4.2.1) that executed a postinstall script as a cross-platform RAT dropper. The dropper contacted a C2 server, delivered platform-specific payloads, deleted itself, and replaced package.json to evade detection. The attack used cscript.exe (VBScript), curl.exe (C2), and PowerShell masquerading as Windows Terminal.
Axios NPM Compromise Indicators - Windows
Detects the specific Windows execution chain and process tree associated with the Axios NPM supply chain compromise. On March 30, 2026, malicious versions (1.14.1, 0.30.4) were published to npm, injecting a dependency (plain-crypto-js@4.2.1) that executed a postinstall script as a cross-platform RAT dropper. The dropper contacted a C2 server, delivered platform-specific payloads, deleted itself, and replaced package.json to evade detection. The attack used cscript.exe (VBScript), curl.exe (C2), and PowerShell masquerading as Windows Terminal.
Successful MSIX/AppX Package Installation
Detects successful MSIX/AppX package installations on Windows systems by monitoring EventID 854 in the Microsoft-Windows-AppXDeployment-Server/Operational log. While most installations are legitimate, this can help identify unauthorized or suspicious package installations. It is crucial to monitor such events as threat actors may exploit MSIX/AppX packages to deliver and execute malicious payloads.
Firewall Rule Modified In The Windows Firewall Exception List
Detects when a rule has been modified in the Windows firewall exception list
Potential Remote WMI ActiveScriptEventConsumers Activity
Detect potential adversaries leveraging WMI ActiveScriptEventConsumers remotely to move laterally in a network. This event is best correlated and used as an enrichment to determine the potential lateral movement activity.
Access To Browser Credential Files By Uncommon Applications - Security
Detects file access requests to browser credential stores by uncommon processes. Could indicate potential attempt of credential stealing This rule requires heavy baselining before usage.
Scheduled Task Deletion
Detects scheduled task deletion events. Scheduled tasks are likely to be deleted if not used for persistence. Malicious Software often creates tasks directly under the root node e.g. \TASKNAME
CreateRemoteThread API and LoadLibrary
Detects potential use of CreateRemoteThread api and LoadLibrary function to inject DLL into a process
Remote Thread Creation Via PowerShell
Detects the creation of a remote thread from a Powershell process to another process
Remote Thread Created In Shell Application
Detects remote thread creation in command shell applications, such as "Cmd.EXE" and "PowerShell.EXE". It is a common technique used by malware, such as IcedID, to inject malicious code and execute it within legitimate processes.
Access To Chromium Browsers Sensitive Files By Uncommon Applications
Detects file access requests to chromium based browser sensitive files by uncommon processes. Could indicate potential attempt of stealing sensitive information.
Access To Browser Credential Files By Uncommon Applications
Detects file access requests to browser credential stores by uncommon processes. Could indicate potential attempt of credential stealing. Requires heavy baselining before usage
Access To Windows Outlook Mail Files By Uncommon Applications
Detects file access requests to Windows Outlook Mail by uncommon processes. Could indicate potential attempt of credential stealing. Requires heavy baselining before usage
Access To Sysvol Policies Share By Uncommon Process
Detects file access requests to the Windows Sysvol Policies Share by uncommon processes
Access To .Reg/.Hive Files By Uncommon Applications
Detects file access requests to files ending with either the ".hive"/".reg" extension, usually associated with Windows Registry backups.
Unattend.XML File Access Attempt
Detects attempts to access the "unattend.xml" file, where credentials might be stored. This file is used during the unattended windows install process.
File Creation Date Changed to Another Year
Detects when the file creation time is changed to a year before 2020. Attackers may change the file creation time of a backdoor to make it look like it was installed with the operating system. Note that many processes legitimately change the creation time of a file; it does not necessarily indicate malicious activity. In order to use this rule in production, it is recommended first baseline normal behavior in your environment and then tune the rule accordingly. Hunting Recommendation: Focus on files with creation times set to years significantly before the current date, especially those in user-writable directories. Correlate with process execution logs to identify the source of the modification and investigate any unsigned or suspicious binaries involved.
ADS Zone.Identifier Deleted
Detects the deletion of the "Zone.Identifier" ADS. Attackers can leverage this in order to bypass security restrictions that make use of the ADS such as Microsoft Office apps.
DMP/HDMP File Creation
Detects the creation of a file with the ".dmp"/".hdmp" extension. 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.
PFX File Creation
Detects the creation of PFX files (Personal Information Exchange format). PFX files contain private keys and certificates bundled together, making them valuable targets for attackers seeking to: - Exfiltrate digital certificates for impersonation or signing malicious code - Establish persistent access through certificate-based authentication - Bypass security controls that rely on certificate validation Analysts should investigate PFX file creation events by examining which process created the PFX file and its parent process chain, as well as unusual locations outside standard certificate stores or development environments.
Python Path Configuration File Creation - Windows
Detects creation of a Python path configuration file (.pth) in Python library folders, which can be maliciously abused for code execution and persistence. Modules referenced by these files are run at every Python startup (v3.5+), regardless of whether the module is imported by the calling script. Default paths are '\lib\site-packages\*.pth' (Windows) and '/lib/pythonX.Y/site-packages/*.pth' (Unix and macOS).
Scheduled Task Created - FileCreation
Detects the creation of a scheduled task via file creation.
Creation of an Executable by an Executable
Detects the creation of an executable by another executable.
Suspicious Creation TXT File in User Desktop
Detects creation of .txt files in user desktop folders via cmd.exe. This behavior may indicate ransomware deploying ransom notes, but can also occur during legitimate administrative tasks. Analysts should investigate for suspicious filenames (e.g., "RANSOM", "DECRYPT", "READ_ME"), bulk file creation patterns, or concurrent encryption activity to determine if this is part of a ransomware attack.
VsCode Code Tunnel Execution File Indicator
Detects the creation of a file with the name "code_tunnel.json" which indicate execution and usage of VsCode tunneling utility. Attackers can abuse this functionality to establish a C2 channel
WDAC Policy File Creation In CodeIntegrity Folder
Attackers can craft a custom Windows Defender Application Control (WDAC) policy that blocks Endpoint Detection and Response (EDR) components while allowing their own malicious code. The policy is placed in the privileged Windows Code Integrity folder (C:\Windows\System32\CodeIntegrity\). Upon reboot, the policy prevents EDR drivers from loading, effectively bypassing security measures and may further enable undetected lateral movement within an Active Directory environment.