While performing functional testing of the ordering feature in the new product, a tester noticed...

Comprehensive and Detailed In-Depth Explanation:

Transmitting data in a human-readable format, such as JSON, over an API can expose sensitive information if the communication channel is not secure. To protect the confidentiality and integrity of the data, it's essential to encrypt all requests and responses between clients and servers.

Implementing encryption, typically through protocols like HTTPS (which utilizes TLS/SSL), ensures that data transmitted over the network is not readable by unauthorized parties. This prevents potential attackers from intercepting and understanding the data, thereby safeguarding sensitive information contained within the API communications.

This practice is a fundamental aspect of secure software development and aligns with the Implementation business function of the OWASP SAMM. Within this function, the Secure Build practice emphasizes the importance of configuring the software to operate securely in its intended environment, which includes enforcing encryption for data in transit.

References:

OWASP SAMM: Implementation - Secure Build