Would the membership software still be considered DSS compliant if it requests the customer's credit card information to be stored in memory prior to handing over the processing to the payment processor and never writes this information to a disk?

In order to be able to handle credit card data as a software, it is essential to be PCI compliant as the software should not have any access to credit card information without complying with the PCI standards for security.

The Issuer Transaction Processor is an important part of the authorization subsystem designed to handle the authorization process of card transactions at the issuer's end. Its primary functions include verifying transaction security through PIN and CVC/CVV codes, monitoring card conditions related to limits, CVC/CVV codes, and other parameters for ensuring holder solvency, and preventing fraud activities.

Additionally, the processor records the transaction processing results in the database and generates a response message.

To address this from a technical standpoint, it's essential to delve into the specifics of data storage and processing.
The decision to not write the credit card information to disk is a positive step in mitigating certain risks associated with persistent storage, such as potential exposure in case of a data breach or unauthorized access. However, focusing solely on disk storage overlooks the broader security implications of storing sensitive data, particularly credit card information, in memory.

Storing credit card details in memory introduces several significant security concerns. From a technical perspective, the volatility and accessibility of memory make it susceptible to attacks such as memory scraping, where malicious software can extract sensitive data directly from a system's memory space. Additionally, any vulnerabilities in the application or underlying system could potentially expose the stored credit card information to unauthorized access.

In the context of compliance with Data Security Standards (DSS), it's essential to evaluate the end-to-end security measures in place for the handling of sensitive data. This includes assessing the encryption mechanisms employed for in-memory storage, as well as the access controls and monitoring measures to prevent unauthorized access or data leakage.

Furthermore, the transition of credit card information to a payment processor should be scrutinized to ensure that it occurs in a secure and compliant manner, with robust encryption and appropriate data protection mechanisms in place during transmission.
While the decision to avoid disk storage of credit card information is a step in the right direction, the storage of such data in memory necessitates thorough security assessments and countermeasures. Compliance with DSS involves a comprehensive approach to data security, encompassing encryption, access controls, vulnerability management, and secure data transmission, to effectively safeguard sensitive information throughout its lifecycle within the membership software application.