The most significant risk to an organization when updating the incident response plan is the undefined assignment of responsibility. An incident response plan is a document that defines the roles, responsibilities, procedures, and resources for responding to an incident that could disrupt the normal operations of the organization, or compromise its assets, reputation, or compliance. An incident response plan should clearly assign the responsibility for each task and activity involved in the incident response process, such as detection, containment, analysis, eradication, recovery, and reporting. Undefined assignment of responsibility could lead to confusion, duplication, conflict, or omission among the stakeholders, and impair the effectiveness and efficiency of the incident response process. Undefined assignment of responsibility could also increase the risk of escalation, recurrence, or impact of the incident, and affect the accountability and performance of the organization. Obsolete response documentation, increased stakeholder turnover, and failure to audit third-party providers are also risks, but they are not as significant as undefined assignment of responsibility, as they do not directly affect the execution and outcome of the incident response process. References = CRISC Review Manual, 6th Edition, ISACA, 2015, page 130.