In today's rapidly evolving threat landscape, having an effective system for collecting, monitoring, and analyzing security events in real-time is crucial. SIEM (Security Information and Event Management) tools offer comprehensive solutions to achieve this goal. This article outlines how to configure SIEM for centralized event collection and analysis on the CentOS 7 operating system.

System Preparation

Before initiating the installation, it's essential to ensure that the system is up-to-date and has sufficient system resources (CPU, memory, disk space) for smooth SIEM tool operation.

1. System Update

   sudo yum update -y
   

2. Installation of Necessary Dependencies Many SIEM tools require specific dependencies. For example:

   sudo yum install epel-release -y
   sudo yum install java-1.8.0-openjdk-headless -y
   ​

 

Choosing a SIEM Tool

There are many SIEM solutions compatible with CentOS. Examples include the ELK Stack (Elasticsearch, Logstash, Kibana) or Wazuh. The choice depends on the organization's specific needs and available resources.

Installation and Configuration of ELK Stack

The ELK Stack is a popular combination of tools for log management and security analysis.

1. Elasticsearch

   • Installation:

     sudo rpm --import https://artifacts.elastic.co/GPG-KEY-elasticsearch
     echo "[elasticsearch-7.x]
     name=Elasticsearch repository for 7.x packages
     baseurl=https://artifacts.elastic.co/packages/7.x/yum
     gpgcheck=1
     gpgkey=https://artifacts.elastic.co/GPG-KEY-elasticsearch
     enabled=1
     autorefresh=1
     type=rpm-md" | sudo tee /etc/yum.repos.d/elasticsearch.repo
     sudo yum install elasticsearch -y
     ​

   • Configuration: Modify the /etc/elasticsearch/elasticsearch.yml file to set up the cluster and network configuration.
   • Start:

     sudo systemctl enable --now elasticsearch
     ​

2. Logstash

   • Installation and configuration are similar to Elasticsearch. Create a configuration file for processing and forwarding logs to Elasticsearch.

3. Kibana

   • Installation and configuration for visualizing data from Elasticsearch.

Security Configuration

Securing your SIEM infrastructure is critical. It includes setting up the firewall, encrypting communication, and user authentication.

1. Firewall Configuration Allow only necessary network traffic to your SIEM services.
2. Encryption using SSL/TLS Configure SSL/TLS for encrypted communication between ELK Stack components and endpoints.
3. Authentication and Authorization Set up strong authentication mechanisms and policies for data access and management.

Log Collection and Analysis

After setting up the ELK Stack, it's time to configure log collection. Logstash can collect logs from various sources, including syslog, Apache/Nginx logs, application logs, etc.

• Create a configuration file for Logstash (/etc/logstash/conf.d/) specifying log sources and output to Elasticsearch.

Visualization and Threat Detection

Kibana provides tools for visualizing collected data. You can create dashboards to monitor security events in real-time and configure rules for threat detection.

• Utilize Kibana to create visualizations and dashboards based on Elasticsearch data.

 

Implementing SIEM solutions on CentOS 7 requires careful preparation and configuration. The ELK Stack is just one of many possible solutions. The key to success lies in meticulous configuration of each component and ongoing system maintenance. With regular monitoring and updates, you can significantly enhance the security of your IT infrastructure.