Detections

Explore public detection logic contributed by the community across SIEM and rule languages.

7,138 detections

Detects the execution of command-line utilities such as 'kill', 'pkill', 'killall', or 'xkill' to terminate or send signals to running processes on a Linux system. This activity can be indicative of an adversary attempting to disrupt services, evade defenses, or clean up their tracks.
avatar
SigmaHQ Detections@sigmaHQ
avatar
SigmaHQ
2 years ago
0031
Detects enumeration of local system accounts on Linux. This information can help adversaries determine which local accounts exist on a system to aid in follow-on behavior. The rule identifies common commands and file accesses used for this purpose, such as 'lastlog', 'id', 'lsof -u', and utilities like 'cat', 'head', 'tail' accessing '/etc/passwd', '/etc/shadow', or '/etc/sudoers'.
avatar
SigmaHQ Detections@sigmaHQ
avatar
SigmaHQ
2 years ago
3029
This rule detects the execution of common Linux utilities used for process discovery. Adversaries often use these commands (atop, htop, pgrep, ps, pstree, top) to gather information about running processes on a system, which helps them understand the environment and plan subsequent actions. This information can reveal common software or applications running on systems within the network.
avatar
SigmaHQ Detections@sigmaHQ
avatar
SigmaHQ
2 years ago
1020
Detects attempts to discover password policy information on Linux systems by monitoring access to key configuration files and the execution of 'chage' and 'passwd' commands with specific arguments.
avatar
SigmaHQ Detections@sigmaHQ
avatar
SigmaHQ
2 years ago
2030
Detects the use of common Linux utilities such as 'find', 'tree', 'findmnt', 'ls -R', and 'mlocate' for discovering files, directories, and potentially network shares. This activity is often performed by adversaries to gain situational awareness of the file system.
avatar
SigmaHQ Detections@sigmaHQ
avatar
SigmaHQ
2 years ago
2026
Detects password policy discovery commands
avatar
SigmaHQ Detections@sigmaHQ
avatar
SigmaHQ
2 years ago
001
Detects usage of system utilities such as "find", "tree", "findmnt", etc, to discover files, directories and network shares.
avatar
SigmaHQ Detections@sigmaHQ
avatar
SigmaHQ
2 years ago
000
This rule detects highly relevant antivirus alerts that specifically report the presence of a web shell. It is designed to flag antivirus detections where the signature indicates a web shell, often identified by keywords related to common web scripting languages (ASP, PHP, JSP, Perl) and terms like 'Backdoor', 'Webshell', or specific web shell names (C99shell, Chopper). The rule emphasizes that such alerts, even if the malware is blocked, warrant further investigation into how the web shell was initially placed on the system.
avatar
SigmaHQ Detections@sigmaHQ
avatar
SigmaHQ
2 years ago
1026
Detects a Python process attempting to spawn a pseudo-terminal (TTY) using the `pty` module. This behavior is often indicative of an attacker establishing a reverse shell for interactive command execution on a compromised system. The rule specifically looks for Python executables and command-line arguments that import the `pty` module and call its `spawn` function.
avatar
SigmaHQ Detections@sigmaHQ
avatar
SigmaHQ
2 years ago
5025
Detects an Antivirus alert in a highly relevant file path or with a relevant file name. This event must not be ignored just because the AV has blocked the malware but investigate, how it came there in the first place.
avatar
SigmaHQ Detections@sigmaHQ
avatar
SigmaHQ
2 years ago
0025
Detects the execution of Python code that imports the 'pty' and 'socket' modules and uses 'spawn' and '.connect' functions, which is a common pattern for establishing a reverse shell.
avatar
SigmaHQ Detections@sigmaHQ
avatar
SigmaHQ
2 years ago
1022
Detects suspicious DNS queries to Monero mining pools
avatar
SigmaHQ Detections@sigmaHQ
avatar
SigmaHQ
2 years ago
102
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.
avatar
SigmaHQ Detections@sigmaHQ
avatar
SigmaHQ
2 years ago
000
Detects the execution of python with calls to the socket and pty module in order to connect and spawn a potential reverse shell.
avatar
SigmaHQ Detections@sigmaHQ
avatar
SigmaHQ
2 years ago
000
This rule detects the execution of various known hacktools on Linux systems by monitoring process creation events and matching against a predefined list of tool names in the 'Image' field. The tools covered include C2 frameworks (e.g., Cobalt Strike, Metasploit, Havoc, Merlin, Sliver), network scanners (e.g., Nmap derivatives, Nuclei, Recon-ng), web enumeration tools (e.g., Dirb, Ffuf, Gobuster), web vulnerability scanners (e.g., Nikto, WPSCan), and other exploit/post-exploitation tools (e.g., Aircrack-ng, Bloodhound-Python, Hashcat, Hydra, John, SQLMap, PEASS-ng).
avatar
SigmaHQ Detections@sigmaHQ
avatar
SigmaHQ
2 years ago
5078
Detects the execution of common network scanning and reconnaissance tools on Linux systems. These tools are often used by adversaries to enumerate local or remote network services, identify open ports, and gather information about network topology and available hosts. The rule specifically looks for the execution of tools like netcat (when not in listen mode), nmap, hping, naabu, autorecon, and telnet.
avatar
SigmaHQ Detections@sigmaHQ
avatar
SigmaHQ
2 years ago
1022
Detects known hacktool execution based on image name.
avatar
SigmaHQ Detections@sigmaHQ
avatar
SigmaHQ
2 years ago
001
This YARA rule detects the GTPDOOR backdoor by identifying specific byte patterns within its code. The rule includes two main detection blocks, one for 'v1' and another for 'v2' versions of the backdoor, each looking for distinct functions related to sending results to a peer, executing remote commands, sending replies, and checking if the daemon is already running. The 'v1' block specifically targets functions like 'send_result_to_peer_v1_p*', 'execute_remote_command_v1', 'send_reply_v1_p*', and 'daemon_already_running_check_v1'. The 'v2' block targets 'send_result_to_peer_v2_p*', 'execute_remote_command_v2', and 'main_routine_v2_p*'. The rule also ensures the file is an ELF executable by checking the magic bytes at the beginning of the file.
ReversingLabs Yara@ReversingLabsYara
avatar
ReversingLabs Yara
2 years ago
0036
Detects execution of network scanning and reconnaisance tools. These tools can be used for the enumeration of local or remote network services for example.
avatar
SigmaHQ Detections@sigmaHQ
avatar
SigmaHQ
2 years ago
000
Detects the use of "vim" and its sibling commands (rvim, vimdiff) to execute a shell or proxy commands. This behavior can be indicative of privilege escalation, unauthorized command execution, or attempts to break out of restricted environments by leveraging the capabilities of these text editors to run arbitrary commands or scripts (e.g., via :!/, :lua, :py, or direct shell calls).
avatar
SigmaHQ Detections@sigmaHQ
avatar
SigmaHQ
2 years ago
2025
Detects the use of the "apt" and "apt-get" commands to execute a shell or proxy commands. Such behavior may be associated with privilege escalation, unauthorized command execution, or to break out from restricted environments.
avatar
SigmaHQ Detections@sigmaHQ
avatar
SigmaHQ
2 years ago
2021
Page 328 of 340