EXPLORE DETECTIONS
Linux Possible Access To Credential Files
The following 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.
Linux Possible Access To Sudoers File
The following analytic detects potential access or modification of the /etc/sudoers file on a Linux system. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on processes like "cat," "nano," "vim," and "vi" accessing the /etc/sudoers file. This activity is significant because the sudoers file controls user permissions for executing commands with elevated privileges. If confirmed malicious, an attacker could gain persistence or escalate privileges, compromising the security of the targeted host.
Linux Possible Append Command To At Allow Config File
The following analytic detects suspicious command lines that append user entries to /etc/at.allow or /etc/at.deny files. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on command-line executions involving these files. This activity is significant because altering these configuration files can allow attackers to schedule tasks with elevated permissions, facilitating persistence on a compromised Linux host. If confirmed malicious, this could enable attackers to execute arbitrary code at scheduled intervals, potentially leading to further system compromise and unauthorized access to sensitive information.
Linux Possible Append Command To Profile Config File
The following analytic detects suspicious command-lines that modify user profile files to automatically execute scripts or executables upon system reboot. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on command-line executions involving profile files like ~/.bashrc and /etc/profile. This activity is significant as it indicates potential persistence mechanisms used by adversaries to maintain access to compromised hosts. If confirmed malicious, this could allow attackers to execute arbitrary code upon reboot, leading to persistent control over the system and potential further exploitation.
Linux Possible Append Cronjob Entry on Existing Cronjob File
The following analytic detects potential tampering with cronjob files on a Linux system by identifying 'echo' commands that append code to existing cronjob files. It leverages logs from Endpoint Detection and Response (EDR) agents, focusing on process names, parent processes, and command-line executions. This activity is significant because adversaries often use it for persistence or privilege escalation. If confirmed malicious, this could allow attackers to execute unauthorized code automatically, leading to system compromises and unauthorized data access, thereby impacting business operations and data integrity.
Linux Possible Cronjob Modification With Editor
The following analytic detects potential unauthorized modifications to Linux cronjobs using text editors like "nano," "vi," or "vim." It identifies this activity by monitoring command-line executions that interact with cronjob configuration paths. This behavior is significant for a SOC as it may indicate attempts at privilege escalation or establishing persistent access. If confirmed malicious, the impact could be severe, allowing attackers to execute damaging actions such as data theft, system sabotage, or further network penetration.
Linux Possible Ssh Key File Creation
The following analytic detects the creation of SSH key files in the ~/.ssh/ directory. It leverages filesystem data to identify new files in this specific path. This activity is significant because threat actors often create SSH keys to gain persistent access and escalate privileges on a compromised host. If confirmed malicious, this could allow attackers to remotely access the machine using the OpenSSH daemon service, leading to potential unauthorized control and data exfiltration.
Linux Preload Hijack Library Calls
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.
Linux Proxy Socks Curl
The following analytic detects the use of the `curl` command with proxy-related arguments such as `-x`, `socks`, `--preproxy`, and `--proxy`. 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 adversary attempting to use a proxy to evade network monitoring and obscure their actions. If confirmed malicious, this behavior could allow attackers to bypass security controls, making it difficult to track their activities and potentially leading to unauthorized data access or exfiltration.
Linux Puppet Privilege Escalation
The following analytic detects the execution of Puppet commands with elevated privileges, specifically when Puppet is used to apply configurations with sudo rights. 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 root access and execute system 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.
Linux RPM Privilege Escalation
The following analytic detects the execution of the RPM Package Manager with elevated privileges, specifically when it is used to run system commands as root via the `--eval` and `lua:os.execute` options. This detection leverages data from Endpoint Detection and Response (EDR) agents, focusing on command-line executions and process metadata. This activity is significant because it indicates a potential privilege escalation attempt, allowing a user to gain root access. If confirmed malicious, this could lead to full system compromise, unauthorized access to sensitive data, and further exploitation of the environment.
Linux Ruby Privilege Escalation
The following analytic detects the execution of Ruby commands with elevated privileges on a Linux system. It identifies processes where Ruby is used with the `-e` flag to execute commands via `sudo`, leveraging Endpoint Detection and Response (EDR) telemetry. This activity is significant because it indicates a potential privilege escalation attempt, allowing a user to execute commands as root. If confirmed malicious, this could lead to full system compromise, enabling an attacker to gain root access, execute arbitrary commands, and maintain persistent control over the affected system.
Linux Service File Created In Systemd Directory
The following analytic detects the creation of suspicious service files within the systemd directories on Linux platforms. It leverages logs containing file name, file path, and process GUID data from endpoints. This activity is significant for a SOC as it may indicate an adversary attempting to establish persistence on a compromised host. If confirmed malicious, this could lead to system compromise or data exfiltration, allowing attackers to maintain control over the system and execute further malicious activities.
Linux Service Restarted
The following analytic detects the restarting or re-enabling of services on Linux systems using the `systemctl` or `service` commands. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on process and command-line execution logs. This activity is significant as adversaries may use it to maintain persistence or execute unauthorized actions. If confirmed malicious, this behavior could lead to repeated execution of malicious payloads, unauthorized access, or data destruction. Security analysts should investigate these events to mitigate risks and prevent further compromise.
Linux Service Started Or Enabled
The following analytic detects the creation or enabling of services on Linux platforms using the systemctl or service tools. It leverages Endpoint Detection and Response (EDR) logs, focusing on process names, parent processes, and command-line executions. This activity is significant as adversaries may create or modify services to maintain persistence or execute malicious payloads. If confirmed malicious, this behavior could lead to persistent access, data theft, ransomware deployment, or other damaging outcomes. Monitoring and investigating such activities are crucial for maintaining the security and integrity of the environment.
Linux 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 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.
Linux Setuid Using Setcap Utility
The following analytic detects the execution of the 'setcap' utility to enable the SUID bit on Linux systems. It leverages Endpoint Detection and Response (EDR) 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 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 Endpoint Detection and Response (EDR) agents, 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 Sqlite3 Privilege Escalation
The following analytic detects the execution of the sqlite3 command with elevated privileges, which can be exploited for privilege escalation. It leverages Endpoint Detection and Response (EDR) telemetry to identify instances where sqlite3 is used in conjunction with shell commands and sudo. This activity is significant because it indicates a potential attempt to gain root access, which could lead to full system compromise. If confirmed malicious, an attacker could execute arbitrary commands as root, leading to unauthorized access, data exfiltration, or further lateral movement within the network.
Linux SSH Authorized Keys Modification
The following analytic detects the modification of SSH Authorized Keys on Linux systems. It leverages process execution data from Endpoint Detection and Response (EDR) agents, specifically monitoring commands like "bash" and "cat" interacting with "authorized_keys" files. This activity is significant as adversaries often modify SSH Authorized Keys to establish persistent access to compromised endpoints. If confirmed malicious, this behavior could allow attackers to maintain unauthorized access, bypassing traditional authentication mechanisms and potentially leading to further exploitation or data exfiltration.
Linux SSH Remote Services Script Execute
The following analytic detects the use of SSH to move laterally and execute a script or file on a remote host. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on specific SSH command-line parameters and URLs. This activity is significant as it may indicate an attacker attempting to execute remote commands or scripts, potentially leading to unauthorized access or control over additional systems. If confirmed malicious, this could result in lateral movement, privilege escalation, or the execution of malicious payloads, compromising the security of the network.
Linux Stdout Redirection To Dev Null File
The following analytic detects command-line activities that redirect stdout or stderr to the /dev/null file. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on process execution logs. This behavior is significant as it can indicate attempts to hide command outputs, a technique observed in the CyclopsBlink malware to conceal modifications to iptables firewall settings. If confirmed malicious, this activity could allow an attacker to stealthily alter system configurations, potentially leading to unauthorized access or persistent control over the compromised machine.
Linux Stop Services
The following analytic detects attempts to stop or clear a service on Linux systems. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on processes like "systemctl," "service," and "svcadm" executing stop commands. This activity is significant as adversaries often 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 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 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.