In PCI DSS, what is an access control list (ACL) used for?

An access control list (ACL) serves a crucial role in security by specifying which users or system processes have access to certain resources within a network or application, particularly concerning sensitive data. In the context of PCI DSS, which is focused on protecting cardholder data, ACLs are integral to limiting access strictly to authorized individuals. By defining permissions and access rights, ACLs help ensure that only those who need to view or manipulate sensitive cardholder information can do so, thereby reducing the risk of unauthorized access and potential data breaches.

This targeted restriction aids organizations in meeting PCI DSS requirements, which emphasize the necessity of protecting sensitive data through controlled access. By implementing an ACL, organizations can enforce the principle of least privilege, which stipulates that users should be granted the minimum level of access necessary for their job functions. This not only enhances the security posture but also aids in compliance with regulatory frameworks like PCI DSS.