So far, there have been a number of areas that have been addressed in terms of preparing for an incident. From an initial understanding of the process involved in incident response, we moved through the creation of an incident response plan and associated playbooks.
Once the capability has been created, it should be run through a table-top exercise to flush out any gaps or deficiencies. This exercise should include a high-level incident scenario that involves the entire team and one of the associated playbooks. A report that details the results of the table-top exercise and any gaps, corrections, or modifications should also be prepared and forwarded to the senior leadership. Once leadership has been informed and acknowledges that the CSIRT is ready to deploy, it is now operational.
As the CSIRT becomes comfortable executing the plan under a structured scenario, they may want to try more complex testing measures. Another option that is available is the Red/Blue or Purple Team exercise. This is where the CSIRT is tasked with responding to an authorized penetration test. Here, the team is able to execute against a live adversary and test the plans and playbooks. This significantly increases the value of the penetration test as it provides both insight into the security of the infrastructure as well as the ability for the organization to respond appropriately.
Regardless of the makeup of the team, another key component of CSIRT deployment is the inclusion of regular training. For CSIRT core members, specific training on emerging threats, forensic techniques, and tools should be ongoing. This can be facilitated through third-party training providers or, if available, in-house training. The technical support members of the CSIRT should receive regular training on techniques and tools available. This is especially important if these members may be called upon during an incident to assist with evidence collection or remediation activities. Finally, the other support members should be included in the annual test of the incident response plan. Just as with the inaugural test, the organization should pick a high-level incident and work through it using a table-top exercise. Another option for the organization is to marry up the test of their incident response plan with a penetration test. If the organization is able to detect the presence of the penetration test, they have the ability to run through the first phases of the incident and craft a tabletop for the remaining portions.
One final component of the ongoing maintenance of the incident response plan is a complete annual review. This annual review is conducted to ensure that any changes in personnel, constituency, or mission that may impact other components of the plan are addressed. In addition to a review of the plan, a complete review of the playbooks is conducted as well. As threats change, it may be necessary to change existing playbooks or add new ones. The CSIRT personnel should also feel free to create a new playbook in the event that a new threat emerges. In this way, the CSIRT will be in a better position to address incidents that may impact their organization. Any major changes or additions should also trigger another table-top exercise to validate the additional plans and playbooks.