Sigma Rules
1,414 rules found for "Nextron Systems"
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.
Suspicious Package Installed - Linux
Detects installation of suspicious packages using system installation utilities
Named Pipe Created Via Mkfifo
Detects the creation of a new named pipe using the "mkfifo" utility
Potentially Suspicious Named Pipe Created Via Mkfifo
Detects the creation of a new named pipe using the "mkfifo" utility in a potentially suspicious location
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.
Potential Perl Reverse Shell Execution
Detects execution of the perl binary with the "-e" flag and common strings related to potential reverse shell activity
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.
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.
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.
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.
Linux Package Uninstall
Detects linux package removal using builtin tools such as "yum", "apt", "apt-get" or "dpkg".
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.
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.
Disable Or Stop Services
Detects the usage of utilities such as 'systemctl', 'service'...etc to stop or disable tools and services on Linux systems. Attackers may stop or disable security tools and services to evade detection, maintain persistence, or disrupt system operations.
Suspicious Curl File Upload - Linux
Detects a suspicious curl process start the adds a file to a web request
Suspicious Curl Change User Agents - Linux
Detects a suspicious curl process start on linux with set useragent options
Potential Discovery Activity Using Find - Linux
Detects usage of "find" binary in a suspicious manner to perform discovery
Suspicious Git Clone - Linux
Detects execution of "git" in order to clone a remote repository that contain suspicious keywords which might be suspicious
History File Deletion
Detects events in which a history file gets deleted, e.g. the ~/bash_history to remove traces of malicious activity
Print History File Contents
Detects events in which someone prints the contents of history files to the commandline or redirects it to a file for reconnaissance
Linux HackTool Execution
Detects known hacktool execution based on image name.
Interactive Bash Suspicious Children
Detects suspicious interactive bash as a parent to rather uncommon child processes
Suspicious Java Children Processes
Detects java process spawning suspicious children
Linux Shell Pipe to Shell
Detects suspicious process command line that starts with a shell that executes something and finally gets piped into another shell
Access of Sudoers File Content
Detects the execution of a text-based file access or inspection utilities to read the content of /etc/sudoers in order to potentially list all users that have sudo rights.
Linux Recon Indicators
Detects events with patterns found in commands used for reconnaissance on linux systems
Script Interpreter Spawning Credential Scanner - Linux
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.
Mask System Power Settings Via Systemctl
Detects the use of systemctl mask to disable system power management targets such as suspend, hibernate, or hybrid sleep. Adversaries may mask these targets to prevent a system from entering sleep or shutdown states, ensuring their malicious processes remain active and uninterrupted. This behavior can be associated with persistence or defense evasion, as it impairs normal system power operations to maintain long-term access or avoid termination of malicious activity.
Triple Cross eBPF Rootkit Execve Hijack
Detects execution of a the file "execve_hijack" which is used by the Triple Cross rootkit as a way to elevate privileges
Triple Cross eBPF Rootkit Install Commands
Detects default install commands of the Triple Cross eBPF rootkit based on the "deployer.sh" script
Vim GTFOBin Abuse - Linux
Detects the use of "vim" and it's siblings 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.
Linux Webshell Indicators
Detects suspicious sub processes of web server processes
Credentials from Password Stores - Keychain
Detects passwords dumps from Keychain
JAMF MDM Potential Suspicious Child Process
Detects potential suspicious child processes of "jamf". Could be a sign of potential abuse of Jamf as a C2 server as seen by Typhon MythicAgent.
Potential Discovery Activity Using Find - MacOS
Detects usage of "find" binary in a suspicious manner to perform discovery
DNS Query to External Service Interaction Domains
Detects suspicious DNS queries to external service interaction domains often used for out-of-band interactions after successful RCE
Cobalt Strike DNS Beaconing
Detects suspicious DNS queries known from Cobalt Strike beacons
Monero Crypto Coin Mining Pool Lookup
Detects suspicious DNS queries to Monero mining pools
Suspicious DNS Query with B64 Encoded String
Detects suspicious DNS queries using base64 encoding
Telegram Bot API Request
Detects suspicious DNS queries to api.telegram.org used by Telegram Bots of any kind
Suspicious DNS Query Indicating Kerberos Coercion via DNS Object SPN Spoofing - Network
Detects DNS queries containing patterns associated with Kerberos coercion attacks via DNS object spoofing. The pattern "1UWhRCAAAAA..BAAAA" is a base64-encoded signature that corresponds to a marshaled CREDENTIAL_TARGET_INFORMATION structure. Attackers can use this technique to coerce authentication from victim systems to attacker-controlled hosts. It is one of the strong indicators of a Kerberos coercion attack, where adversaries manipulate DNS records to spoof Service Principal Names (SPNs) and redirect authentication requests like CVE-2025-33073.
Apache Segmentation Fault
Detects a segmentation fault error message caused by a crashing apache worker process
Apache Threading Error
Detects an issue in apache logs that reports threading related errors
Nginx Core Dump
Detects a core dump of a crashing Nginx worker process, which could be a signal of a serious problem or exploitation attempts.
Windows WebDAV User Agent
Detects WebDav DownloadCradle
Download from Suspicious Dyndns Hosts
Detects download of certain file types from hosts with dynamic DNS names (selected list)
Download From Suspicious TLD - Blacklist
Detects download of certain file types from hosts in suspicious TLDs
Download From Suspicious TLD - Whitelist
Detects executable downloads from suspicious remote systems