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Event: exec_from_unusual_dir

Quick Explanation

The exec_from_unusual_dir recipe identifies the execution of files from non-standard directories like /tmp, /dev, and /proc, which are not typically used for file execution. Such behavior is suspicious and may indicate attempts to run malicious code. Detection of this activity suggests potential unauthorized code execution, threatening the integrity of both the build and production environments.

More Information

Information

  1. Description: Execution from unusual directory
  2. Category: Execution
  3. Method: User Execution
  4. Importance: High, Critical

Analysis of the Event

This detection event is triggered when files are executed from unusual directories, such as /tmp, /dev, /sys, /proc, and certain subdirectories within /var, /usr, and other special Linux directories. These directories are not typically used for executing files in standard operations, making any such activity suspicious.

The detection relies on monitoring file actions, specifically execve system calls, within these directories using eBPF tracing techniques. Jibril employs recipes to define these rules and triggers an alert if any file within the specified directories attempts to execute.

Such behavior could indicate an attempt to execute malicious code or scripts from temporary or system-critical directories, which are often targeted by attackers due to their accessibility and potential impact on the system.

Implications for the CI/CD Pipeline

If this security event is triggered during a pull request in the CI/CD pipeline, it suggests that recent code changes might include scripts or binaries being executed from non-standard directories. This poses a significant risk as it could lead to unauthorized code execution, potentially compromising the build environment and leading to further exploitation in production if deployed. The integrity of both the CI environment and production systems could be jeopardized, resulting in data breaches or service disruptions.

  1. Review Code Changes:
  2. Examine recent commits and pull requests for any scripts or binaries that might be executing from unusual directories.
  3. Ensure that all executable files are placed in appropriate directories (/usr/bin, /usr/sbin, etc.).
  4. Audit Dependencies:
  5. Check dependencies included in the recent changes for any scripts or binaries that may execute from temporary or system-critical directories.
  6. Validate that all third-party tools adhere to security best practices regarding file placement and execution.
  7. Implement Directory Whitelisting:
  8. Configure Jibril or other security tools to enforce stricter controls over executable file locations.
  9. Whitelist only necessary directories where executables are allowed to run.
  10. Enhance Monitoring:
  11. Increase monitoring of directory activities within your CI/CD pipeline.
  12. Set up alerts for any unauthorized executions detected by Jibril.
  13. Conduct Security Training:
  14. Educate developers about secure coding practices, especially regarding file execution locations.
  15. Provide guidelines on how to avoid common pitfalls related to directory usage.

By following these steps, you can mitigate the risks introduced by the pull request and ensure a more secure CI/CD pipeline environment.