The GCP IAM and Tag Enumeration rule is designed to detect suspicious enumeration of Identity and Access Management (IAM) policies and tags within Google Cloud Platform (GCP). This behavior can be indicative of reconnaissance activities by unauthorized actors aiming to discover potential avenues for privilege escalation through tag-based access control. The detection mechanism relies on monitoring specific log types associated with GCP Audit Logs to identify actions related to IAM policy and tag key enumeration. These actions include the calls to methods such as 'GetIamPolicy' for IAM policies and 'TagKeys.ListTagKeys' for tag enumeration. In cases where unauthorized enumeration is detected, it is crucial to investigate the legitimacy of the user's actions and to review corresponding IAM policies to prevent potential security incidents. The severity of this detection is classified as 'Info' since it may not immediately indicate a direct threat but could signify preparatory actions for future attacks.