File Integrity Monitoring with Wazuh SIEM Tool

Overview

One of the most critical security requirements in the current threat landscape is safeguarding essential system files from unwanted modifications. Changes to files, directories, and system configurations are tracked by File Integrity Monitoring (FIM), which assists businesses in identifying questionable activities. An open-source Security Information and Event Management (SIEM) program that offers thorough monitoring and threat detection capabilities, Wazuh is a strong and affordable option for this purpose.

This post explains the architecture, configuration, and best practices for deploying File Integrity Monitoring in Wazuh.

Screenshot
The front page of the Wazuh Dashboard displays the system overview with agents attached and modules such as Vulnerability Detection, Sysmon, and FIM accessible.

What is File Integrity Monitoring (FIM)?

File Integrity Monitoring is a security control that continuously checks the integrity of critical files to detect:

• Unauthorized modifications, additions, or deletions.
• Changes to sensitive system configurations (e.g., /etc/passwd in Linux or Windows registry keys).
• Unexpected alterations that could indicate malware infection, insider threats, or policy violations.

Regulatory standards such as PCI DSS, HIPAA, and ISO 27001 also mandate the use of FIM as part of compliance requirements.

Descriptive image
A conceptual diagram of FIM — arrows showing monitored files → Wazuh Agent → Wazuh Manager → Dashboard alerts

Why Should You Use Wazuh for File Integrity Monitoring?

Wazuh's log gathering, alerting, and threat detection functions are easily integrated with an integrated FIM module. Advantages consist of:

• Monitoring in real time: Identifies file modifications as they take place.
  • **Centralized administration: **The Wazuh dashboard gathers, correlates, and displays alerts.
  • Cross-platform compatibility: compatible with Windows, Linux, and macOS.
  • Scalability: able to accommodate both small settings and big businesses with thousands of endpoints.
  • **Integration: **Establishes connections with Kibana (or OpenSearch Dashboard), Elasticsearch, and additional SIEM elements.

*Screenshot: *
Wazuh Dashboard panel showing "File Integrity Monitoring" alerts — list of modified files, their hashes, and severity levels.

The Wazuh FIM Architecture

The FIM component in Wazuh operates in three main layers:

Agent Layer

• Installed on monitored endpoints.
• Watches files, directories, and registry keys.
• Collects events on changes such as creation, modification, or deletion.

Manager Layer

• Central Wazuh manager receives FIM data from agents.
• Applies rules, correlation, and threat intelligence to classify events.

Dashboard (Kibana/OpenSearch)

• Visualizes alerts and changes in real-time.
• Provides search, filtering, and reporting features for incident response.

Diagram Screenshot:
Architecture diagram with three layers: Endpoint Agent > Wazuh Manager > Elasticsearch/Kibana. Could you highlight how file changes move across the system?

The Best Ways to Deploy Wazuh FIM

- Set important assets first: Pay close attention to registry keys, configuration files, system binaries, and sensitive files.
- Make use of hashes and checksums: ** Set Wazuh up to calculate file hashes (SHA1/SHA256) for more robust integrity checks.
Adjust frequency parameters to strike a balance between detection requirements and performance (e.g., hourly scans for essential systems).
Connect FIM alerts to Indicators of Compromise (IoCs) to integrate with threat intelligence.
**- Automate responses: If a critical file is changed, isolate a host by using Wazuh Active Responses to initiate an action.
- Review notifications frequently. Tune rules and rule out benign modifications to prevent alert fatigue.

In conclusion

A critical security measure that aids businesses in identifying unauthorized changes to vital files and configurations is file integrity monitoring. Wazuh's integrated FIM module provides a reliable, scalable, and reasonably priced solution for monitoring file modifications across various settings.

Security teams can improve their detection skills, satisfy compliance standards, and fortify their overall security posture by properly configuring and fine-tuning Wazuh FIM.