Sigma Rules
3,116 rules found for "sigma"
Suspicious Copy From or To System Directory
Detects a suspicious copy operation that tries to copy a program from system (System32, SysWOW64, WinSxS) directories to another on disk. Often used to move LOLBINs such as 'certutil' or 'desktopimgdownldr' to a different location with a different name in order to bypass detections based on locations.
LOL-Binary Copied From System Directory
Detects a suspicious copy operation that tries to copy a known LOLBIN from system (System32, SysWOW64, WinSxS) directories to another on disk in order to bypass detections based on locations.
Potential Crypto Mining Activity
Detects command line parameters or strings often used by crypto miners
Potential Data Exfiltration Activity Via CommandLine Tools
Detects the use of various CLI utilities exfiltrating data via web requests
Raccine Uninstall
Detects commands that indicate a Raccine removal from an end system. Raccine is a free ransomware protection tool.
Suspicious Double Extension File Execution
Detects suspicious use of an .exe extension after a non-executable file extension like .pdf.exe, a set of spaces or underlines to cloak the executable file in spear phishing campaigns
Suspicious Parent Double Extension File Execution
Detect execution of suspicious double extension files in ParentCommandLine
Suspicious Download from Office Domain
Detects suspicious ways to download files from Microsoft domains that are used to store attachments in Emails or OneNote documents
DumpStack.log Defender Evasion
Detects the use of the filename DumpStack.log to evade Microsoft Defender
Always Install Elevated MSI Spawned Cmd And Powershell
Detects Windows Installer service (msiexec.exe) spawning "cmd" or "powershell"
Suspicious Electron Application Child Processes
Detects suspicious child processes of electron apps (teams, discord, slack, etc.). This could be a potential sign of ".asar" file tampering (See reference section for more information) or binary execution proxy through specific CLI arguments (see related rule)
Potentially Suspicious Electron Application CommandLine
Detects potentially suspicious CommandLine of electron apps (teams, discord, slack, etc.). This could be a sign of abuse to proxy execution through a signed binary.
Elevated System Shell Spawned From Uncommon Parent Location
Detects when a shell program such as the Windows command prompt or PowerShell is launched with system privileges from a uncommon parent location.
Hidden Powershell in Link File Pattern
Detects events that appear when a user click on a link file with a powershell command in it
Potential Defense Evasion Activity Via Emoji Usage In CommandLine - 1
Detects the usage of emojis in the command line, this could be a sign of potential defense evasion activity.
Potential Defense Evasion Activity Via Emoji Usage In CommandLine - 2
Detects the usage of emojis in the command line, this could be a sign of potential defense evasion activity.
Potential Defense Evasion Activity Via Emoji Usage In CommandLine - 3
Detects the usage of emojis in the command line, this could be a sign of potential defense evasion activity.
Potential Defense Evasion Activity Via Emoji Usage In CommandLine - 4
Detects the usage of emojis in the command line, this could be a sign of potential defense evasion activity.
ETW Logging Tamper In .NET Processes Via CommandLine
Detects changes to environment variables related to ETW logging via the CommandLine. This could indicate potential adversaries stopping ETW providers recording loaded .NET assemblies.
ETW Trace Evasion Activity
Detects command line activity that tries to clear or disable any ETW trace log which could be a sign of logging evasion.
Suspicious Eventlog Clearing or Configuration Change Activity
Detects the clearing or configuration tampering of EventLog using utilities such as "wevtutil", "powershell" and "wmic". This technique were seen used by threat actors and ransomware strains in order to evade defenses.
Potentially Suspicious EventLog Recon Activity Using Log Query Utilities
Detects execution of different log query utilities and commands to search and dump the content of specific event logs or look for specific event IDs. This technique is used by threat actors in order to extract sensitive information from events logs such as usernames, IP addresses, hostnames, etc.
Potentially Suspicious Execution From Parent Process In Public Folder
Detects a potentially suspicious execution of a parent process located in the "\Users\Public" folder executing a child process containing references to shell or scripting binaries and commandlines.
Process Execution From A Potentially Suspicious Folder
Detects a potentially suspicious execution from an uncommon folder.
Suspicious File Characteristics Due to Missing Fields
Detects Executables in the Downloads folder without FileVersion,Description,Product,Company likely created with py2exe
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.
Suspicious Reconnaissance Activity Via GatherNetworkInfo.VBS
Detects execution of the built-in script located in "C:\Windows\System32\gatherNetworkInfo.vbs". Which can be used to gather information about the target machine
Potential Hidden Directory Creation Via NTFS INDEX_ALLOCATION Stream - CLI
Detects command line containing reference to the "::$index_allocation" stream, which can be used as a technique to prevent access to folders or files from tooling such as "explorer.exe" or "powershell.exe"
Writing Of Malicious Files To The Fonts Folder
Monitors for the hiding possible malicious files in the C:\Windows\Fonts\ location. This folder doesn't require admin privillege to be written and executed from.
Potential Homoglyph Attack Using Lookalike Characters
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.
Execution Of Non-Existing File
Checks whether the image specified in a process creation event is not a full, absolute path (caused by process ghosting or other unorthodox methods to start a process)
Base64 MZ Header In CommandLine
Detects encoded base64 MZ header in the commandline
Potentially Suspicious Inline JavaScript Execution via NodeJS Binary
Detects potentially suspicious inline JavaScript execution using Node.js with specific keywords in the command line.
Potential WinAPI Calls Via CommandLine
Detects the use of WinAPI Functions via the commandline. As seen used by threat actors via the tool winapiexec
Potentially Suspicious JWT Token Search Via CLI
Detects potentially suspicious search for JWT tokens via CLI by looking for the string "eyJ0eX" or "eyJhbG". JWT tokens are often used for access-tokens across various applications and services like Microsoft 365, Azure, AWS, Google Cloud, and others. Threat actors may search for these tokens to steal them for lateral movement or privilege escalation.
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.
Local Accounts Discovery
Local accounts, System Owner/User discovery using operating systems utilities
LOLBIN Execution From Abnormal Drive
Detects LOLBINs executing from an abnormal or uncommon drive such as a mounted ISO.
LSASS Dump Keyword In CommandLine
Detects the presence of the keywords "lsass" and ".dmp" in the commandline, which could indicate a potential attempt to dump or create a dump of the lsass process.
Potential File Download Via MS-AppInstaller Protocol Handler
Detects usage of the "ms-appinstaller" protocol handler via command line to potentially download arbitrary files via AppInstaller.EXE The downloaded files are temporarly stored in ":\Users\%username%\AppData\Local\Packages\Microsoft.DesktopAppInstaller_8wekyb3d8bbwe\AC\INetCache\<RANDOM-8-CHAR-DIRECTORY>"
Suspicious Network Command
Adversaries may look for details about the network configuration and settings of systems they access or through information discovery of remote systems
Suspicious Scan Loop Network
Adversaries may attempt to get a listing of other systems by IP address, hostname, or other logical identifier on a network that may be used for Lateral Movement from the current system
Potential Network Sniffing Activity Using Network Tools
Detects potential network sniffing via use of network tools such as "tshark", "windump". Network sniffing refers to using the network interface on a system to monitor or capture information sent over a wired or wireless connection. An adversary may place a network interface into promiscuous mode to passively access data in transit over the network, or use span ports to capture a larger amount of data.
Process Launched Without Image Name
Detect the use of processes with no name (".exe"), which can be used to evade Image-based detections.
Execution of Suspicious File Type Extension
Detects whether the image specified in a process creation event doesn't refer to an ".exe" (or other known executable extension) file. This can be caused by process ghosting or other unorthodox methods to start a process. This rule might require some initial baselining to align with some third party tooling in the user environment.
Non-privileged Usage of Reg or Powershell
Search for usage of reg or Powershell by non-privileged users to modify service configuration in registry
Suspicious Process Patterns NTDS.DIT Exfil
Detects suspicious process patterns used in NTDS.DIT exfiltration
Potentially Suspicious Call To Win32_NTEventlogFile Class
Detects usage of the WMI class "Win32_NTEventlogFile" in a potentially suspicious way (delete, backup, change permissions, etc.) from a PowerShell script