The first step in the incident response process for a suspected breach is to research the validity of the alerted breach. An incident response process is a set of procedures that defines how to handle security incidents in a timely and effective manner. The first step in this process is to research the validity of the alerted breach, which means to verify whether the alert is genuine or false positive, to determine the scope and impact of the incident, and to gather relevant information for further analysis and action. Informing potentially affected customers of the security breach, notifying business management of the security breach, and engaging a third party to independently evaluate the alerted breach are also steps in the incident response process, but they are not the first step. References:
* CISA Review Manual, 27th Edition, page 4251
* CISA Review Questions, Answers & Explanations Database - 12 Month Subscription