An IR custodian is typically responsible for making decisions on the classifications and the severity of the incident identified. This role involves determining the impact of the incident, categorizing its severity, and guiding the appropriate response according to the organization's incident response plan. The custodian plays a critical role in the incident response process by ensuring that incidents are properly identified, classified, and escalated to the relevant parties for further action.
References: The information provided aligns with the objectives and documents of the EC-Council's Certified Network Defender (CND) program, which includes understanding the roles and responsibilities within an incident response team. For more detailed information, refer to the official CND study guide and materials provided by the EC-Council.