The AWS WAF Disassociation detection rule is designed to identify and alert on disassociation events for web application firewalls (WAFs) in an AWS environment. This event is crucial to monitor, as it may indicate unauthorized changes to the configuration or misconfigurations that could expose web applications to potential attacks. The rule specifically looks for the AWS CloudTrail event 'DisassociateWebACL', which indicates that a web access control list (ACL) has been disassociated from a resource. The intent of monitoring such disassociation actions is to enforce security measures and ensure that any potentially harmful changes are reported immediately. The detection is enabled and set with a threshold of 1, meaning any occurrence of this event within the defined deduplication period of 60 minutes will trigger an alert. The rule is classified as critical to emphasize the importance of maintaining the integrity of WAF engagements.