This detection rule monitors changes to the ingress and egress rules of AWS security groups via CloudTrail logs. It specifically looks for event names related to modifying security group rules, such as 'AuthorizeSecurityGroupEgress', 'AuthorizeSecurityGroupIngress', 'RevokeSecurityGroupEgress', and 'RevokeSecurityGroupIngress'. Unauthorized modifications can suggest malicious activities such as opening new attack vectors for data exfiltration or enabling communication with command-and-control (C&C) servers. Alerting on these events helps in early detection of potential breaches or misconfigurations that could expose sensitive resources to unnecessary risks.