Rule Library

Sigma Rules

3,132 rules found for "sigma"

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

ESXi Network Configuration Discovery Via ESXCLI

Detects execution of the "esxcli" command with the "network" flag in order to retrieve information about the network configuration.

LinuxProcess Creation
Cedric MaurugeonMon Sep 04linux
Detectionhightest

ESXi Admin Permission Assigned To Account Via ESXCLI

Detects execution of the "esxcli" command with the "system" and "permission" flags in order to assign admin permissions to an account.

LinuxProcess Creation
Nasreddine Bencherchali (Nextron Systems)Mon Sep 04linux
Detectionmediumtest

ESXi Storage Information Discovery Via ESXCLI

Detects execution of the "esxcli" command with the "storage" flag in order to retrieve information about the storage status and other related information. Seen used by malware such as DarkSide and LockBit.

LinuxProcess Creation
Nasreddine Bencherchali (Nextron Systems)+1Mon Sep 04linux
Detectionmediumtest

ESXi Syslog Configuration Change Via ESXCLI

Detects changes to the ESXi syslog configuration via "esxcli"

LinuxProcess Creation
Cedric MaurugeonMon Sep 04linux
Detectionmediumtest

ESXi System Information Discovery Via ESXCLI

Detects execution of the "esxcli" command with the "system" flag in order to retrieve information about the different component of the system. Such as accounts, modules, NTP, etc.

LinuxProcess Creation
Cedric MaurugeonMon Sep 04linux
Detectionmediumtest

ESXi Account Creation Via ESXCLI

Detects user account creation on ESXi system via esxcli

LinuxProcess Creation
Cedric MaurugeonTue Aug 22linux
Detectionmediumtest

ESXi VM List Discovery Via ESXCLI

Detects execution of the "esxcli" command with the "vm" flag in order to retrieve information about the installed VMs.

LinuxProcess Creation
Cedric MaurugeonMon Sep 04linux
Detectionmediumtest

ESXi VM Kill Via ESXCLI

Detects execution of the "esxcli" command with the "vm" and "kill" flag in order to kill/shutdown a specific VM.

LinuxProcess Creation
Nasreddine Bencherchali (Nextron Systems)+1Mon Sep 04linux
Detectionmediumtest

ESXi VSAN Information Discovery Via ESXCLI

Detects execution of the "esxcli" command with the "vsan" flag in order to retrieve information about virtual storage. Seen used by malware such as DarkSide.

LinuxProcess Creation
Nasreddine Bencherchali (Nextron Systems)+1Mon Sep 04linux
Detectioninformationaltest

File and Directory Discovery - Linux

Detects usage of system utilities such as "find", "tree", "findmnt", etc, to discover files, directories and network shares.

LinuxProcess Creation
Daniil Yugoslavskiy+2Mon Oct 19linux
Detectioninformationalstable

File Deletion

Detects file deletion using "rm", "shred" or "unlink" commands which are used often by adversaries to delete files left behind by the actions of their intrusion activity

LinuxProcess Creation
Ömer Günal+1Wed Oct 07linux
Detectionhightest

Shell Execution via Find - Linux

Detects the use of the find command to execute a shell. Such behavior may be associated with privilege escalation, unauthorized command execution, or exploitation attempt.

LinuxProcess Creation
Li Ling+3Mon Sep 02linux
Detectionhightest

Shell Execution via Flock - Linux

Detects the use of the "flock" command to execute a shell. Such behavior may be associated with privilege escalation, unauthorized command execution, or to break out from restricted environments.

LinuxProcess Creation
Li Ling+3Mon Sep 02linux
Detectionhightest

Shell Execution GCC - Linux

Detects the use of the "gcc" utility to execute a shell. Such behavior may be associated with privilege escalation, unauthorized command execution, or to break out from restricted environments.

LinuxProcess Creation
Li Ling+3Mon Sep 02linux
Detectionhightest

Shell Execution via Git - Linux

Detects the use of the "git" utility to execute a shell. Such behavior may be associated with privilege escalation, unauthorized command execution, or to break out from restricted environments.

LinuxProcess Creation
Li Ling+3Mon Sep 02linux
Detectionlowtest

OS Architecture Discovery Via Grep

Detects the use of grep to identify information about the operating system architecture. Often combined beforehand with the execution of "uname" or "cat /proc/cpuinfo"

LinuxProcess Creation
Joseliyo SanchezFri Jun 02linux
Detectionmediumtest

Group Has Been Deleted Via Groupdel

Detects execution of the "groupdel" binary. Which is used to delete a group. This is sometimes abused by threat actors in order to cover their tracks

LinuxProcess Creation
Tuan Le (NCSGroup)Mon Dec 26linux
Detectionlowtest

Install Root Certificate

Detects installation of new certificate on the system which attackers may use to avoid warnings when connecting to controlled web servers or C2s

LinuxProcess Creation
Ömer Günal+1Mon Oct 05linux
Detectionmediumtest

Suspicious Package Installed - Linux

Detects installation of suspicious packages using system installation utilities

LinuxProcess Creation
Nasreddine Bencherchali (Nextron Systems)Tue Jan 03linux
Detectionmediumtest

Flush Iptables Ufw Chain

Detect use of iptables to flush all firewall rules, tables and chains and allow all network traffic

LinuxProcess Creation
Joseliyo SanchezWed Jan 18linux
Detectionlowtest

Local System Accounts Discovery - Linux

Detects enumeration of local system accounts. This information can help adversaries determine which local accounts exist on a system to aid in follow-on behavior.

LinuxProcess Creation
Alejandro Ortuno+2Thu Oct 08linux
Detectionlowtest

Local Groups Discovery - Linux

Detects enumeration of local system groups. Adversaries may attempt to find local system groups and permission settings

LinuxProcess Creation
Ömer Günal+2Sun Oct 11linux
Detectionhightest

Potential GobRAT File Discovery Via Grep

Detects the use of grep to discover specific files created by the GobRAT malware

LinuxProcess Creation
Joseliyo SanchezFri Jun 02linux
Detectionlowtest

Named Pipe Created Via Mkfifo

Detects the creation of a new named pipe using the "mkfifo" utility

LinuxProcess Creation
Nasreddine Bencherchali (Nextron Systems)Fri Jun 16linux
Detectionmediumtest

Potentially Suspicious Named Pipe Created Via Mkfifo

Detects the creation of a new named pipe using the "mkfifo" utility in a potentially suspicious location

LinuxProcess Creation
Nasreddine Bencherchali (Nextron Systems)Fri Jun 16linux
Detectionmediumtest

Mount Execution With Hidepid Parameter

Detects execution of the "mount" command with "hidepid" parameter to make invisible processes to other users from the system

LinuxProcess Creation
Joseliyo SanchezThu Jan 12linux
Detectionhightest

Potential Netcat Reverse Shell Execution

Detects execution of netcat with the "-e" flag followed by common shells. This could be a sign of a potential reverse shell setup.

LinuxProcess Creation
@d4ns4n_+1Fri Apr 07linux
Detectionhightest

Shell Execution via Nice - Linux

Detects the use of the "nice" utility to execute a shell. Such behavior may be associated with privilege escalation, unauthorized command execution, or to break out from restricted environments.

LinuxProcess Creation
Li Ling+3Mon Sep 02linux
Detectionmediumtest

Nohup Execution

Detects usage of nohup which could be leveraged by an attacker to keep a process running or break out from restricted environments

LinuxProcess Creation
Christopher Peacock+1Mon Jun 06linux
Detectionhightest

Suspicious Nohup Execution

Detects execution of binaries located in potentially suspicious locations via "nohup"

LinuxProcess Creation
Joseliyo SanchezFri Jun 02linux
Detectionhightest

OMIGOD SCX RunAsProvider ExecuteScript

Rule to detect the use of the SCX RunAsProvider ExecuteScript to execute any UNIX/Linux script using the /bin/sh shell. Script being executed gets created as a temp file in /tmp folder with a scx* prefix. Then it is invoked from the following directory /etc/opt/microsoft/scx/conf/tmpdir/. The file in that directory has the same prefix scx*. SCXcore, started as the Microsoft Operations Manager UNIX/Linux Agent, is now used in a host of products including Microsoft Operations Manager, Microsoft Azure, and Microsoft Operations Management Suite.

LinuxProcess Creation
Roberto Rodriguez (Cyb3rWard0g)+2Fri Oct 15linux
Detectionhightest

OMIGOD SCX RunAsProvider ExecuteShellCommand

Rule to detect the use of the SCX RunAsProvider Invoke_ExecuteShellCommand to execute any UNIX/Linux command using the /bin/sh shell. SCXcore, started as the Microsoft Operations Manager UNIX/Linux Agent, is now used in a host of products including Microsoft Operations Manager, Microsoft Azure, and Microsoft Operations Management Suite.

LinuxProcess Creation
Roberto Rodriguez (Cyb3rWard0g)+2Fri Oct 15linux
Detectionhightest

Potential Perl Reverse Shell Execution

Detects execution of the perl binary with the "-e" flag and common strings related to potential reverse shell activity

LinuxProcess Creation
@d4ns4n_+1Fri Apr 07linux
Detectionhightest

Potential PHP Reverse Shell

Detects usage of the PHP CLI with the "-r" flag which allows it to run inline PHP code. The rule looks for calls to the "fsockopen" function which allows the creation of sockets. Attackers often leverage this in combination with functions such as "exec" or "fopen" to initiate a reverse shell connection.

LinuxProcess Creation
@d4ns4n_Fri Apr 07linux
Detectionmediumtest

Pnscan Binary Data Transmission Activity

Detects command line patterns associated with the use of Pnscan for sending and receiving binary data across the network. This behavior has been identified in a Linux malware campaign targeting Docker, Apache Hadoop, Redis, and Confluence and was previously used by the threat actor known as TeamTNT

LinuxProcess Creation
David BurkettTue Apr 16linux
Detectionlowtest

Connection Proxy

Detects setting proxy configuration

LinuxProcess Creation
Ömer GünalWed Jun 17linux
Detectionmediumexperimental

PUA - TruffleHog Execution - Linux

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.

LinuxProcess Creation
Swachchhanda Shrawan Poudel (Nextron Systems)Wed Sep 24linux
Detectionhighexperimental

Python One-Liners with Base64 Decoding - Linux

Detects the use of Python's base64 decoding functions in command line executions on Linux systems. Malicious scripts often use python one-liners to decode and execute base64-encoded payloads, which is a common technique for obfuscation and evasion.

LinuxProcess Creation
Hugh Ryan (HueCodes)+1Mon Mar 09linux
Detectionmediumexperimental

Python WebServer Execution - Linux

Detects the execution of Python web servers via command line interface (CLI). After gaining access to target systems, adversaries may use Python's built-in HTTP server modules to quickly establish a web server without requiring additional software. This technique is commonly used in post-exploitation scenarios as it provides a simple method for transferring files between the compromised host and attacker-controlled systems.

LinuxProcess Creation
Mohamed LAKRIFri Oct 17linux
Detectionmediumtest

Python Spawning Pretty TTY Via PTY Module

Detects a python process calling to the PTY module in order to spawn a pretty tty which could be indicative of potential reverse shell activity.

LinuxProcess Creation
Nextron SystemsFri Jun 03linux
Detectionhightest

Python Reverse Shell Execution Via PTY And Socket Modules

Detects the execution of python with calls to the socket and pty module in order to connect and spawn a potential reverse shell.

LinuxProcess Creation
@d4ns4n_+1Mon Apr 24linux
Detectionhightest

Inline Python Execution - Spawn Shell Via OS System Library

Detects execution of inline Python code via the "-c" in order to call the "system" function from the "os" library, and spawn a shell.

LinuxProcess Creation
Li Ling+3Mon Sep 02linux
Detectionlowtest

Remote Access Tool - Team Viewer Session Started On Linux Host

Detects the command line executed when TeamViewer starts a session started by a remote host. Once a connection has been started, an investigator can verify the connection details by viewing the "incoming_connections.txt" log file in the TeamViewer folder.

LinuxProcess Creation
Josh Nickels+1Mon Mar 11linux
Detectionlowtest

Linux Remote System Discovery

Detects the enumeration of other remote systems.

LinuxProcess Creation
Alejandro Ortuno+1Thu Oct 22linux
Detectionlowtest

Linux Package Uninstall

Detects linux package removal using builtin tools such as "yum", "apt", "apt-get" or "dpkg".

LinuxProcess Creation
Tuan Le (NCSGroup)+1Thu Mar 09linux
Detectionhighexperimental

Shell Execution via Rsync - Linux

Detects the use of the "rsync" utility to execute a shell. Such behavior may be associated with privilege escalation, unauthorized command execution, or to break out from restricted environments.

LinuxProcess Creation
Li Ling+4Mon Sep 02linux
Detectionhighexperimental

Suspicious Invocation of Shell via Rsync

Detects the execution of a shell as sub process of "rsync" without the expected command line flag "-e" being used, which could be an indication of exploitation as described in CVE-2024-12084. This behavior is commonly associated with attempts to execute arbitrary commands or escalate privileges, potentially leading to unauthorized access or further exploitation.

LinuxProcess Creation
Florian Roth (Nextron Systems)Sat Jan 18linux
Detectionmediumtest

Potential Ruby Reverse Shell

Detects execution of ruby with the "-e" flag and calls to "socket" related functions. This could be an indication of a potential attempt to setup a reverse shell

LinuxProcess Creation
@d4ns4n_Fri Apr 07linux