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SigmaHQ Detections

@sigmaHQ
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6,800 detections

This rule detects the execution of the 'unzip' command where the target file has a common image file extension ('.jpg' or '.png'). This behavior is indicative of an attempt to extract hidden information, specifically a zip archive, from an image file, a technique often used in steganography for defense evasion or data exfiltration.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
2 years ago
1025
Detects the execution of PHP CLI with the "-r" flag to run inline PHP code, specifically looking for calls to the "fsockopen" function. This combination is often used by attackers to create sockets for reverse shell connections, potentially in conjunction with functions like "exec" or "fopen". The rule also checks for common Unix shell names in the command line, indicating an attempt to spawn a shell.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
2 years ago
2025
Detects the creation or modification of scheduled cron jobs where the command line argument contains '/tmp/'. This behavior is often indicative of an adversary attempting to establish persistence or execute malicious code from a temporary directory using the cron utility.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
2 years ago
1025
Detects the execution of the 'curl' command on Linux systems when it includes options to set a custom user agent. This behavior can be indicative of command and control communication or data exfiltration attempts where an adversary tries to mimic legitimate web traffic or evade detection by changing the default user agent string.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
2 years ago
1025
This rule detects the use of the 'find' command on Linux systems with specific permission-related arguments. These arguments are often used by attackers during the discovery phase to locate files with unusual permissions, such as SUID/SGID binaries (-perm -4000, -perm -2000, -perm -u=s, -perm -g=s) which can be exploited for privilege escalation, or world-writable files (-perm 0777, -perm -222, -perm -o w) which could be used for persistence or data modification. It also looks for world-executable files (-perm -o x).
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
2 years ago
2025
Detects the execution of common Linux utilities used to discover system network connections and logged-in users. Specifically, it looks for 'who', 'w', 'last', 'lsof', and 'netstat' commands. It filters out legitimate calls from '/usr/bin/landscape-sysinfo' when 'who' is used.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
2 years ago
1025
Detects the usage of the 'usermod' command to add a user to either the 'root' or 'sudoers' group on a Linux system. This activity can indicate privilege escalation or persistence mechanisms by an attacker.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
2 years ago
1025
This rule detects the use of 'dd' and 'truncate' utilities to add junk data to a file, a technique known as binary padding. Adversaries may use this method to alter the on-disk representation of malware, potentially bypassing security tools that have file size limitations or rely on hash-based detection.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
2 years ago
1025
Detects the execution of the 'jamf' binary with specific commands that could be used by attackers for privilege escalation, bypassing security controls, or modifying system configurations. This includes creating user accounts, managing the JAMF framework, removing MDM profiles, resetting passwords, and setting computer names.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
2 years ago
1025
This rule detects the execution of system commands commonly used to shut down, reboot, or halt a macOS system. Adversaries may use these commands to disrupt system availability or aid in the destruction of systems.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
2 years ago
0025
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