According to PCI-DSS requirement 1.3.5, what type of traffic should be prevented from the cardholder data environment?

The correct answer is focused on preventing all unauthorized outbound traffic from the cardholder data environment. This requirement is critical in maintaining the security and integrity of sensitive payment card information.

PCI-DSS, which stands for Payment Card Industry Data Security Standard, has stringent measures in place to protect cardholder data. Requirement 1.3.5 specifically emphasizes controlling and monitoring outbound traffic to ensure that any data leakage or unauthorized access does not occur. By prohibiting unauthorized outbound traffic, organizations can significantly reduce the risk of data breaches, where sensitive information may be transmitted outside the secure environment.

This approach aligns with the broader goal of ensuring that only legitimate, authorized transactions and communications are permitted, ultimately safeguarding cardholder data from potential theft or misuse. It is crucial for organizations handling payment card data to implement robust network security measures that not only monitor but also restrict access based on predefined security policies.

In contrast, other options might suggest allowing certain types of traffic, thus potentially exposing the cardholder data environment to greater risks. Maintaining strict boundaries regarding what is allowed to leave that environment is essential for compliance and protection of sensitive card data.