Best Practices for Successful SIEM Implementation
- Establish the Scope and Requirements
Know exactly what activities and logs you want your SIEM to monitor. This includes choosing if you want to implement your SIEM as an on-premise software or a hosted or managed service.
Next, you should get a clear picture of the requirements for your SIEM, including the use cases for your particular industry. In addition, you should take note of compliance requirements, comparing them with the candidate SIEM solutions you are considering. Some vendors offer built-in features that support specific compliance requirements, including auditing.
- Customize Correlation Rules
The core value of SIEM stems from applying correlation rules that can flag security events that otherwise go unnoticed. For instance, a correlation rule that says that if there are several failed logins from the same IP in a given timeframe followed by a successful login, a brute force attack may be in progress. While SIEM software comes with its own set of built-in rules, you can customize it to your needs by removing false positives or creating new rules.
- Do a Test Run First
A pilot run in a section of the infrastructure is a good way to test the new deployment. This stage provides the proof of concept, and the potential ROI for the system. However, it is important that this test subset represents the wider system context to allow for identifying flaws and vulnerabilities in security policies.
During this test run, collect as much data as possible to allow for a clear picture of how the system would run. Of course, it is not always possible to collect data from every single source across the organization. In this case, you should prioritize sections dealing with the critical systems and sensitive data.
- Have an Incident Response Plan in Place
A SIEM provides near real-time monitoring and alerts for IT threat detection, allowing for a rapid response to a myriad of security events. However, the organization should leverage SIEM features by implementing a detailed, hands-on Incident Response Plan.
This comprehensive protocol should cover issues such as distributing the responsibilities and tasks in the event of a data breach or attack, prioritizing and documenting the event, and delegating who will be responsible for communicating the breach to stakeholders and relevant authorities. A well-laid incident response plan provides the exact steps and guidelines for the security teams to follow when an attack occurs, saving time and minimizing mistakes resulting from ad-hoc responses.
- Update Your SIEM System Continuously
Since attackers are constantly improving their methods and techniques, the SIEM needs to remain a step ahead. You should periodically test your SIEM, modelling potential attacks and evaluating the SIEM reaction. Simulating attacks can help you to refine the SIEM configuration by tweaking the correlation rules, policies and procedures to keep ahead of malicious attackers.