EXPLORE DETECTIONS
Linux Auditd Setuid Using Chmod Utility
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 Linux Auditd, 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.
Linux Auditd Setuid Using Setcap Utility
The following analytic detects the execution of the 'setcap' utility to enable the SUID bit on Linux systems. It leverages Linux Auditd data, focusing on process names and command-line arguments that indicate the use of 'setcap' with specific capabilities. This activity is significant because setting the SUID bit allows a user to temporarily gain root access, posing a substantial security risk. If confirmed malicious, an attacker could escalate privileges, execute arbitrary commands with elevated permissions, and potentially compromise the entire system.
Linux Auditd Shred Overwrite Command
The following 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.
Linux Auditd Stop Services
The following analytic detects attempts to stop a service on Linux systems. It leverages data from Linux Auditd. This activity is significant as adversaries often stop or terminate security or critical services to disable defenses or disrupt operations, as seen in malware like Industroyer2. If confirmed malicious, this could lead to the disabling of security mechanisms, allowing attackers to persist, escalate privileges, or deploy destructive payloads, severely impacting system integrity and availability.
Linux Auditd Sudo Or Su Execution
The following analytic detects the execution of the "sudo" or "su" command on a Linux operating system. It leverages data from Linux Auditd, 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.
Linux Auditd Sysmon Service Stop
The following analytic detects the suspicious sysmon service stop. This behavior is critical for a SOC to monitor because it may indicate attempts to gain unauthorized access or maintain control over a system. Such actions could be signs of malicious activity. If confirmed, this could lead to serious consequences, including a compromised system, unauthorized access to sensitive data, or even a wider breach affecting the entire network. Detecting and responding to these signs early is essential to prevent potential security incidents.
Linux Auditd System Network Configuration Discovery
The following analytic detects suspicious system network configuration discovery activities, which may indicate an adversary's attempt to gather information about the network environment. Such actions typically involve commands or tools used to identify network interfaces, routing tables, and active connections. Detecting these activities is crucial, as they often precede more targeted attacks like lateral movement or data exfiltration. By identifying unusual or unauthorized network discovery efforts, this analytic helps security teams to swiftly detect and respond to potential reconnaissance operations, mitigating the risk of further compromise.
Linux Auditd Unix Shell Configuration Modification
The following analytic detects suspicious access or modifications to Unix shell configuration files, which may indicate an attempt to alter system behavior or gain unauthorized access. Unix shell configuration files, such as `.bashrc` or `.profile`, control user environment settings and command execution. Unauthorized changes to these files can be used to execute malicious commands, escalate privileges, or hide malicious activities. By monitoring for unusual or unauthorized modifications to shell configuration files, this analytic helps identify potential security threats, allowing security teams to respond quickly and mitigate risks. Correlate this with related EXECVE or PROCTITLE events to identify the process or user responsible for the access or modification.
Linux Auditd Unload Module Via Modprobe
The following analytic detects suspicious use of the `modprobe` command to unload kernel modules, which may indicate an attempt to disable critical system components or evade detection. The `modprobe` utility manages kernel modules, and unauthorized unloading of modules can disrupt system security features, remove logging capabilities, or conceal malicious activities. By monitoring for unusual or unauthorized `modprobe` operations involving module unloading, this analytic helps identify potential tampering with kernel functionality, enabling security teams to investigate and address possible threats to system integrity.
Linux Auditd Virtual Disk File And Directory Discovery
The following analytic detects suspicious discovery of virtual disk files and directories, which may indicate an attacker's attempt to locate and access virtualized storage environments. Virtual disks can contain sensitive data or critical system configurations, and unauthorized discovery attempts could signify preparatory actions for data exfiltration or further compromise. By monitoring for unusual or unauthorized searches for virtual disk files and directories, this analytic helps identify potential reconnaissance activities, enabling security teams to respond promptly and safeguard against unauthorized access and data breaches.
Linux Auditd Whoami User Discovery
The following analytic detects the suspicious use of the whoami command, which may indicate an attacker trying to gather information about the current user account on a compromised system. The whoami command is commonly used to verify user privileges and identity, especially during initial stages of an attack to assess the level of access. By monitoring for unusual or unauthorized executions of whoami, this analytic helps in identifying potential reconnaissance activities, enabling security teams to take action before the attacker escalates privileges or conducts further malicious operations.
Linux AWK Privilege Escalation
The following analytic detects the use of the AWK command with elevated privileges to execute system commands. It leverages Endpoint Detection and Response (EDR) telemetry, specifically monitoring processes that include "sudo," "awk," and "BEGIN*system" in their command lines. This activity is significant because it indicates a potential privilege escalation attempt, where a user could gain root access by executing commands as the root user. If confirmed malicious, this could allow an attacker to fully compromise the system, execute arbitrary commands, and maintain persistent control over the affected endpoint.
Linux Busybox Privilege Escalation
The following analytic detects the execution of BusyBox with sudo privileges, which can lead to privilege escalation on Linux systems. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on process creation events where BusyBox is executed with both 'sh' and 'sudo' commands. This activity is significant because it indicates a user may be attempting to gain root access, bypassing standard security controls. If confirmed malicious, this could allow an attacker to execute arbitrary commands as root, leading to full system compromise and potential persistence within the environment.
Linux c89 Privilege Escalation
The following analytic detects the execution of the 'c89' command with elevated privileges, which can be used to compile and execute C programs as root. This detection leverages data from Endpoint Detection and Response (EDR) agents, focusing on process creation events that include command-line arguments. This activity is significant because it indicates a potential privilege escalation attempt, allowing a user to execute arbitrary commands as root. If confirmed malicious, this could lead to full system compromise, enabling the attacker to gain root access and execute any command with elevated privileges.
Linux c99 Privilege Escalation
The following analytic detects the execution of the c99 utility with sudo privileges, which can lead to privilege escalation on Linux systems. 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 it indicates a potential misuse of the c99 utility to gain root access, which is critical for maintaining system security. If confirmed malicious, this could allow an attacker to execute commands as root, potentially compromising the entire system and accessing sensitive information.
Linux Change File Owner To Root
The following analytic detects the use of the 'chown' command to change a file owner to 'root' on a Linux system. It leverages Endpoint Detection and Response (EDR) telemetry, specifically monitoring command-line executions and process details. This activity is significant as it may indicate an attempt to escalate privileges by adversaries, malware, or red teamers. If confirmed malicious, this action could allow an attacker to gain root-level access, leading to full control over the compromised host and potential persistence within the environment.
Linux Clipboard Data Copy
The following analytic detects the use of the Linux 'xclip' command to copy data from the clipboard. It leverages Endpoint Detection and Response (EDR) 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.
Linux Common Process For Elevation Control
The following analytic identifies the execution of common Linux processes used for elevation control, such as `chmod`, `chown`, and `setuid`. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on process names and command-line executions. This activity is significant because these processes are often abused by adversaries to gain persistence or escalate privileges on compromised hosts. If confirmed malicious, this behavior could allow attackers to modify file attributes, change file ownership, or set user IDs, potentially leading to unauthorized access and control over critical system resources.
Linux Composer Privilege Escalation
The following analytic detects the execution of the Composer tool with elevated privileges on a Linux system. It identifies instances where Composer is run with the 'sudo' command, allowing the user to execute system commands as root. This detection leverages data from Endpoint Detection and Response (EDR) agents, focusing on process execution logs and command-line arguments. This activity is significant because it can indicate an attempt to escalate privileges, potentially leading to unauthorized root access. If confirmed malicious, an attacker could gain full control over the system, execute arbitrary commands, and compromise sensitive data.
Linux Cpulimit Privilege Escalation
The following analytic detects the use of the 'cpulimit' command with specific flags ('-l', '-f') executed with 'sudo' privileges. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on process command-line arguments and execution details. 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.
Linux Csvtool Privilege Escalation
The following analytic detects the execution of the 'csvtool' command with 'sudo' privileges, which can allow a user to run system commands as root. This detection leverages data from Endpoint Detection and Response (EDR) agents, focusing on process execution logs that include command-line details. This activity is significant because it indicates a potential privilege escalation attempt, where a user could gain unauthorized root access. If confirmed malicious, this could lead to full system compromise, allowing an attacker to execute arbitrary commands, escalate privileges, and maintain persistent access.
Linux Curl Upload File
The following analytic detects the use of the curl command with specific switches (-F, --form, --upload-file, -T, -d, --data, --data-raw, -I, --head) to upload AWS credentials or configuration files to a remote destination. This detection leverages data from Endpoint Detection and Response (EDR) agents, focusing on command-line executions and process details. This activity is significant as it may indicate an attempt to exfiltrate sensitive AWS credentials, a technique known to be used by the TeamTNT group. If confirmed malicious, this could lead to unauthorized access and potential compromise of AWS resources.
Linux Data Destruction Command
The following analytic detects the execution of a Unix shell command designed to wipe root directories on a Linux host. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on the 'rm' command with force recursive deletion and the '--no-preserve-root' option. This activity is significant as it indicates potential data destruction attempts, often associated with malware like Awfulshred. If confirmed malicious, this behavior could lead to severe data loss, system instability, and compromised integrity of the affected Linux host. Immediate investigation and response are crucial to mitigate potential damage.
Linux DD File Overwrite
The following analytic detects the use of the 'dd' command to overwrite files on a Linux system. 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 often use the 'dd' command to destroy or irreversibly overwrite files, disrupting system availability and services. If confirmed malicious, this behavior could lead to data destruction, making recovery difficult and potentially causing significant operational disruptions.