To secure a Fargate, you should use the AWS Identity and Access Management (IAM) service to control access to resources associated with your Fargate service. Additionally, you should configure a VPC with private subnets, security groups, and Network Access Control Lists (ACLs) for your VPC and subnets to limit traffic to and from the Fargate service. Consider using Amazon ECR to automatically store Docker images of your container tasks to scan them for vulnerabilities. Utilize AWS Secrets Manager or an AWS KMS customer master key (CMK) to encrypt sensitive data stored in databases, files, or configuration settings associated with the Fargate service. Finally, you should monitor your Fargate tasks' performance using CloudWatch logs to detect any suspicious activity.