Set up a verified identity for the third-party ticketing system's email in Amazon Simple Email Service (SES). Configure an Amazon EventBridge rule with an event pattern to detect High severity GuardDuty findings and set the SES identity as the target.

Establish an Amazon Simple Notification Service (SNS) topic and subscribe the third-party ticketing system's email to it. Create an Amazon EventBridge rule with an event pattern to detect High severity GuardDuty findings and designate the SNS topic as the target.

Utilize the GuardDuty CreateFilter API to create a filter that monitors for High severity findings. Export the filtered results to an Amazon Simple Notification Service (SNS) topic and subscribe the third-party ticketing system's email to it.

Employ the GuardDuty CreateFilter API to create a filter for High severity findings. Set up an Amazon Simple Notification Service (SNS) topic and subscribe the third-party ticketing system's email to it. Then, create an Amazon EventBridge rule with an event pattern to match the filtered GuardDuty findings and set the SNS topic as the target.