Rule Library

Sigma Rules

1,414 rules found for "Nextron Systems"

3,731Total
3,132Detection
457Emerging
139Hunting
Detectionhighstable

Potential Crypto Mining Activity

Detects command line parameters or strings often used by crypto miners

WindowsProcess Creation
Florian Roth (Nextron Systems)Tue Oct 26windows
Detectionhightest

Potential Data Exfiltration Activity Via CommandLine Tools

Detects the use of various CLI utilities exfiltrating data via web requests

WindowsProcess Creation
Nasreddine Bencherchali (Nextron Systems)Tue Aug 02windows
Detectionhightest

Raccine Uninstall

Detects commands that indicate a Raccine removal from an end system. Raccine is a free ransomware protection tool.

WindowsProcess Creation
Florian Roth (Nextron Systems)Thu Jan 21windows
Detectionhighstable

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

WindowsProcess Creation
Florian Roth (Nextron Systems)+2Wed Jun 26windows
Detectionhightest

Suspicious Parent Double Extension File Execution

Detect execution of suspicious double extension files in ParentCommandLine

WindowsProcess Creation
François Hubaut+1Fri Jan 06windows
Detectionhightest

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

WindowsProcess Creation
Florian Roth (Nextron Systems)+1Mon Dec 27windows
Detectioncriticaltest

DumpStack.log Defender Evasion

Detects the use of the filename DumpStack.log to evade Microsoft Defender

WindowsProcess Creation
Florian Roth (Nextron Systems)Thu Jan 06windows
Detectionmediumtest

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)

WindowsProcess Creation
Nasreddine Bencherchali (Nextron Systems)Fri Oct 21windows
Detectionmediumtest

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.

WindowsProcess Creation
François Hubaut+1Tue Sep 05windows
Detectionhightest

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.

WindowsProcess Creation
@neu5ron+3Fri Mar 22windows
Detectionhighstable

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.

WindowsProcess Creation
Ecco+4Thu Sep 26windows
Detectionmediumtest

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.

WindowsProcess Creation
Nasreddine Bencherchali (Nextron Systems)+1Fri Sep 09windows
Detectionhightest

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.

WindowsProcess Creation
Florian Roth (Nextron Systems)+1Fri Feb 25windows
Detectionhightest

Process Execution From A Potentially Suspicious Folder

Detects a potentially suspicious execution from an uncommon folder.

WindowsProcess Creation
Florian Roth (Nextron Systems)+1Wed Jan 16windows
Detectionhighexperimental

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.

WindowsProcess Creation
0xFustang+1Mon Nov 24windows
Detectionhightest

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

WindowsProcess Creation
Nasreddine Bencherchali (Nextron Systems)Wed Feb 08windows
Detectionmediumtest

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"

WindowsProcess Creation
Nasreddine Bencherchali (Nextron Systems)+1Mon Oct 09windows
Detectionhightest

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)

WindowsProcess Creation
Max Altgelt (Nextron Systems)Thu Dec 09windows
Detectionhightest

Base64 MZ Header In CommandLine

Detects encoded base64 MZ header in the commandline

WindowsProcess Creation
Nasreddine Bencherchali (Nextron Systems)Tue Jul 12windows
Detectionmediumexperimental

Potentially Suspicious Inline JavaScript Execution via NodeJS Binary

Detects potentially suspicious inline JavaScript execution using Node.js with specific keywords in the command line.

WindowsProcess Creation
Microsoft+1Mon Apr 21windows
Detectionhightest

Potential WinAPI Calls Via CommandLine

Detects the use of WinAPI Functions via the commandline. As seen used by threat actors via the tool winapiexec

WindowsProcess Creation
Nasreddine Bencherchali (Nextron Systems)Tue Sep 06windows
Detectionmediumtest

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.

WindowsProcess Creation
Nasreddine Bencherchali (Nextron Systems)+1Tue Oct 25windows
Detectionhighexperimental

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.

WindowsProcess Creation
Swachchhanda Shrawan Poudel (Nextron Systems)Wed Mar 19windows
Detectionhightest

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.

WindowsProcess Creation
E.M. Anhaus+3Thu Oct 24windows
Detectionmediumtest

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>"

WindowsProcess Creation
Nasreddine Bencherchali (Nextron Systems)+1Thu Nov 09windows
Detectionmediumtest

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.

WindowsProcess Creation
Timur Zinniatullin+2Mon Oct 21windows
Detectionmediumtest

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.

WindowsProcess Creation
Max Altgelt (Nextron Systems)Thu Dec 09windows
Detectionhightest

Suspicious Process Patterns NTDS.DIT Exfil

Detects suspicious process patterns used in NTDS.DIT exfiltration

WindowsProcess Creation
Florian Roth (Nextron Systems)Fri Mar 11windows
Detectionhightest

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

WindowsProcess Creation
Nasreddine Bencherchali (Nextron Systems)Thu Jul 13windows
Detectionmediumtest

Use Short Name Path in Image

Detect use of the Windows 8.3 short name. Which could be used as a method to avoid Image detection

WindowsProcess Creation
François Hubaut+1Sun Aug 07windows
Detectionmediumtest

Use NTFS Short Name in Command Line

Detect use of the Windows 8.3 short name. Which could be used as a method to avoid command-line detection

WindowsProcess Creation
François Hubaut+1Fri Aug 05windows
Detectionmediumtest

Use NTFS Short Name in Image

Detect use of the Windows 8.3 short name. Which could be used as a method to avoid Image based detection

WindowsProcess Creation
François Hubaut+1Sat Aug 06windows
Detectionmediumtest

Obfuscated IP Download Activity

Detects use of an encoded/obfuscated version of an IP address (hex, octal...) in an URL combined with a download command

WindowsProcess Creation
Florian Roth (Nextron Systems)+1Wed Aug 03windows
Detectionmediumtest

Obfuscated IP Via CLI

Detects usage of an encoded/obfuscated version of an IP address (hex, octal, etc.) via command line

WindowsProcess Creation
Nasreddine Bencherchali (Nextron Systems)+1Wed Aug 03windows
Detectionhightest

Suspicious Process Parents

Detects suspicious parent processes that should not have any children or should only have a single possible child program

WindowsProcess Creation
Florian Roth (Nextron Systems)Mon Mar 21windows
Detectionhightest

Potential PowerShell Execution Via DLL

Detects potential PowerShell execution from a DLL instead of the usual PowerShell process as seen used in PowerShdll. This detection assumes that PowerShell commands are passed via the CommandLine.

WindowsProcess Creation
Markus Neis+1Sat Aug 25windows
Detectionmediumtest

Private Keys Reconnaissance Via CommandLine Tools

Adversaries may search for private key certificate files on compromised systems for insecurely stored credential

WindowsProcess Creation
François Hubaut+1Tue Jul 20windows
Detectionmediumtest

Suspicious RunAs-Like Flag Combination

Detects suspicious command line flags that let the user set a target user and command as e.g. seen in PsExec-like tools

WindowsProcess Creation
Florian Roth (Nextron Systems)Fri Nov 11windows
Detectionhightest

Suspicious Program Names

Detects suspicious patterns in program names or folders that are often found in malicious samples or hacktools

WindowsProcess Creation
Florian Roth (Nextron Systems)Fri Feb 11windows
Detectionhightest

Suspicious Process Execution From Fake Recycle.Bin Folder

Detects process execution from a fake recycle bin folder, often used to avoid security solution.

WindowsProcess Creation
X__Junior (Nextron Systems)Wed Jul 12windows
Detectionhightest

Suspicious Redirection to Local Admin Share

Detects a suspicious output redirection to the local admins share, this technique is often found in malicious scripts or hacktool stagers

WindowsProcess Creation
Florian Roth (Nextron Systems)Sun Jan 16windows
Detectionmediumtest

Registry Modification of MS-settings Protocol Handler

Detects registry modifications to the 'ms-settings' protocol handler, which is frequently targeted for UAC bypass or persistence. Attackers can modify this registry to execute malicious code with elevated privileges by hijacking the command execution path.

WindowsProcess Creation
François Hubaut+1Mon Dec 20windows
Detectionhightest

Potential Defense Evasion Via Right-to-Left Override

Detects the presence of the "u202+E" character, which causes a terminal, browser, or operating system to render text in a right-to-left sequence. This character is used as an obfuscation and masquerading techniques by adversaries to trick users into opening malicious files.

WindowsProcess Creation
Micah Babinski+2Wed Feb 15windows
Detectionhightest

Script Interpreter Execution From Suspicious Folder

Detects suspicious script execution from suspicious directories or folders accessible by environment variables that may indicate malware activity. Script interpreters (cscript, wscript, mshta, powershell) executing from folders like Temp, Public, or user profile directories may suggest attempts to evade detection or execute malicious scripts.

WindowsProcess Creation
Florian Roth (Nextron Systems)+1Tue Feb 08windows
Detectionhighexperimental

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.

WindowsProcess Creation
Swachchhanda Shrawan Poudel (Nextron Systems)Tue Nov 25windows
Detectionhightest

Sensitive File Access Via Volume Shadow Copy Backup

Detects a command that accesses the VolumeShadowCopy in order to extract sensitive files such as the Security or SAM registry hives or the AD database (ntds.dit)

WindowsProcess Creation
Max Altgelt (Nextron Systems)+1Mon Aug 09windows
Detectionhightest

Suspicious New Service Creation

Detects creation of a new service via "sc" command or the powershell "new-service" cmdlet with suspicious binary paths

WindowsProcess Creation
Nasreddine Bencherchali (Nextron Systems)Thu Jul 14windows
Detectionhightest

Suspicious Service Binary Directory

Detects a service binary running in a suspicious directory

WindowsProcess Creation
Florian Roth (Nextron Systems)Tue Mar 09windows