Detections

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

7,270 detections

The analytic detects the creation of the /etc/at.allow or /etc/at.deny configuration files in Linux. These files control user permissions for the "at" scheduling application and can be abused by attackers to establish persistence. If confirmed malicious, this could allow unauthorized execution of malicious code, leading to potential data theft or further system compromise. Analysts should review the file path, creation time, and associated processes to assess the threat.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0036
The following analytic detects the execution of the "At" application in Linux, which can be used by attackers to create persistence entries on a compromised host. This detection leverages data from Endpoint Detection and Response (EDR) agents, focusing on process names and parent process names associated with "at" or "atd". This activity is significant because the "At" application can be exploited to maintain unauthorized access or deliver additional malicious payloads. If confirmed malicious, this behavior could lead to data theft, ransomware attacks, or other severe consequences. Immediate investigation is required to determine the legitimacy of the execution and mitigate potential risks.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0036
This analytic detects the execution of the 'shred' command on a Linux machine, which is used to overwrite files to make them unrecoverable. It leverages data from Linux Auditd, focusing on process names and command-line arguments. This activity is significant because the 'shred' command can be used in destructive attacks, such as those seen in the Industroyer2 malware targeting energy facilities. If confirmed malicious, this activity could lead to the permanent destruction of critical files, severely impacting system integrity and data availability.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0036
The following analytic detects the deletion of cron jobs on a Linux machine. It leverages filesystem event logs to identify when files within the "/etc/cron.*" directory are deleted. This activity is significant because attackers or malware may delete cron jobs to disable scheduled security tasks or evade detection mechanisms. If confirmed malicious, this action could allow an attacker to disrupt system operations, evade security measures, or facilitate further malicious activities such as data wiping, as seen with the acidrain malware.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0036
The following analytic detects attempts to escalate privileges on a Linux system using Docker. It identifies processes where Docker commands are used to mount the root directory or execute shell commands within a container. This detection leverages Endpoint Detection and Response (EDR) telemetry, focusing on process names, command-line arguments, and parent processes. This activity is significant because it can allow an attacker with Docker privileges to modify critical system files, such as /etc/passwd, to create a superuser. If confirmed malicious, this could lead to full system compromise and persistent unauthorized access.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0036
The analytic detects the execution of the 'gawk' command with elevated privileges on a Linux system. It identifies command-line executions where 'gawk' is used with 'sudo' and 'BEGIN{system' patterns. This activity indicates a potential privilege escalation attempt, allowing a user to execute system commands as root. If confirmed malicious, this could lead to full root access, enabling the attacker to control the system, modify critical files, and maintain persistent access.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
1036
The analytic detects attempts to access or dump the contents of /etc/passwd and /etc/shadow files on Linux systems. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on processes like 'cat', 'nano', 'vim', and 'vi' accessing these files. This activity is significant as it may indicate credential dumping, a technique used by adversaries to gain persistence or escalate privileges. If confirmed malicious, attackers could obtain hashed passwords for offline cracking, leading to unauthorized access and potential system compromise.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
1036
The following analytic detects the execution of the chmod utility to set the SUID or SGID bit on files, which can allow users to temporarily gain root or group-level access. This detection leverages data from Endpoint Detection and Response (EDR) agents, focusing on process names and command-line arguments related to chmod. This activity is significant as it can indicate an attempt to escalate privileges or maintain persistence on a system. If confirmed malicious, an attacker could gain elevated access, potentially compromising sensitive data or critical system functions.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0036
The following analytic detects the execution of the "sudo" or "su" command on a Linux operating system. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on process names and parent process names. This activity is significant because "sudo" and "su" commands are commonly used by adversaries to elevate privileges, potentially leading to unauthorized access or control over the system. If confirmed malicious, this activity could allow attackers to execute commands with root privileges, leading to severe security breaches, data exfiltration, or further system compromise.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0036
The following analytic detects the use of the 'find' command with 'sudo' and '-exec' options, which can indicate an attempt to escalate privileges on a Linux system. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on process execution logs that include command-line arguments. This activity is significant because it can allow a user to execute system commands as root, potentially leading to a root shell. If confirmed malicious, this could enable an attacker to gain full control over the system, leading to severe security breaches and unauthorized access to sensitive data.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0035
The following analytic detects a high frequency of file deletions in the /boot/ folder on Linux systems. It leverages filesystem event logs to identify when 200 or more files are deleted within an hour by the same process. This behavior is significant as it may indicate the presence of wiper malware, such as Industroyer2, which targets critical system directories. If confirmed malicious, this activity could lead to system instability or failure, hindering the boot process and potentially causing a complete system compromise.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0035
The analytic detects suspicious command-line activity that modifies the iptables firewall settings on a Linux machine. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on specific command patterns that alter firewall rules to accept traffic on certain TCP ports. This activity is significant as it can indicate malware, such as CyclopsBlink, modifying firewall settings to allow communication with a Command and Control (C2) server. If confirmed malicious, this could enable attackers to maintain persistent access and exfiltrate data, posing a severe security risk.
Splunk Security@SplunkSecurity
avatar
Splunk Security Content
1 year ago
0035
The analytic detects the use of the Linux 'xclip' command to copy data from the clipboard. It leverages Linux Auditd telemetry, focusing on process names and command-line arguments related to clipboard operations. This activity is significant because adversaries can exploit clipboard data to capture sensitive information such as passwords or IP addresses. If confirmed malicious, this technique could lead to unauthorized data exfiltration, compromising sensitive information and potentially aiding further attacks within the environment.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0034
The analytic detects the execution of the 'c89' command with elevated privileges, specifically when used in conjunction with 'sudo' and a '-wrapper' argument. This activity indicates a potential privilege escalation attempt on Linux systems, allowing a user to compile and execute C programs as root. Successful exploitation could lead to full system compromise.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0034
The analytic detects the use of the 'cpulimit' command with specific flags ('-l', '-f') executed with 'sudo' privileges on Linux systems. This activity is significant because if 'cpulimit' is granted sudo rights, a user can potentially execute system commands as root, leading to privilege escalation. If confirmed malicious, this could allow an attacker to gain root access, execute arbitrary commands, and fully compromise the affected system.
Splunk Security@SplunkSecurity
avatar
Splunk Security Content
1 year ago
0034
This analytic detects the behavior of decoding base64-encoded data and passing it to a Linux shell. The detection is made by searching for specific commands in the Splunk query, namely "base64 -d" and "base64 --decode", within the Endpoint.Processes data model. The analytic also includes a filter for Linux shells. This activity is indicative of malicious behavior as Base64 encoding is commonly used to obfuscate malicious commands or payloads, and decoding it can be a step in running those commands. It suggests that an attacker is attempting to run malicious commands on a Linux system to gain unauthorized access, for data exfiltration, or perform other malicious actions.
Splunk Security@SplunkSecurity
avatar
Splunk Security Content
1 year ago
0034
The following analytic detects the deletion of init daemon scripts on a Linux machine. It leverages filesystem event logs to identify when files within the /etc/init.d/ directory are deleted. This activity is significant because init daemon scripts control the start and stop of critical services, and their deletion can indicate an attempt to impair security features or evade defenses. If confirmed malicious, this behavior could allow an attacker to disrupt essential services, execute destructive payloads, or persist undetected in the environment.
Splunk Security@SplunkSecurity
avatar
Splunk Security Content
1 year ago
0034
The analytic detects the suspicious editing of cron jobs in Linux using the `crontab` command-line parameter (`-e`). It identifies this activity by monitoring command-line executions involving 'crontab' and the edit parameter. This behavior is significant for a SOC as cron job manipulations can indicate unauthorized persistence attempts or scheduled malicious actions. If confirmed malicious, this activity could lead to system compromise, unauthorized access, or broader network compromise.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0034
The following analytic detects the use of the LD_PRELOAD environment variable to hijack or hook library functions on a Linux platform. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on process execution logs that include command-line details. This activity is significant because adversaries, malware authors, and red teamers commonly use this technique to gain elevated privileges and establish persistence on a compromised machine. If confirmed malicious, this behavior could allow attackers to execute arbitrary code, escalate privileges, and maintain long-term access to the system.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0034
The analytic identifies potential enumeration of local network configuration on Linux systems. It detects this activity by monitoring processes such as "arp," "ifconfig," "ip," "netstat," "firewall-cmd," "ufw," "iptables," "ss," and "route" within a 30-minute window. This behavior is significant as it often indicates reconnaissance efforts by adversaries to gather network information for subsequent attacks. If confirmed malicious, this activity could enable attackers to map the network, identify vulnerabilities, and plan further exploitation or lateral movement within the environment.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0034
The analytic detects attempts to disable a service on a Linux system. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on processes like "systemctl," "service," and "svcadm" with commands containing "disable." This activity is significant as adversaries may disable security or critical services to evade detection and facilitate further malicious actions, such as deploying destructive payloads. If confirmed malicious, this could lead to the termination of essential security services, allowing attackers to persist undetected and potentially cause significant damage to the system.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
1033
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