Securing the Next Generation of Digital Payments: A Comprehensive Threat Model for Virtual Card Ecosystems

Virtual card technologies have revolutionized B2B payments by offering enhanced control, automation, and security compared to traditional methods. However, their digital nature creates a complex ecosystem with unique security challenges spanning multiple stakeholders. This article develops a systematic threat model for virtual card ecosystems using the STRIDE methodology to categorize vulnerabilities throughout the payment lifecycle. By analyzing the ecosystem's structure—including corporate buyers, suppliers, financial institutions, and technology platforms—the article identifies critical assets and maps data flows across organizational boundaries. The threat model examines authentication vulnerabilities, transaction integrity risks, confidentiality concerns, availability threats, and authorization weaknesses. To address these challenges, a multi-layered defense-in-depth strategy is proposed, combining foundational controls like PCI DSS compliance, technical measures such as tokenization and secure API design, and advanced protection mechanisms including AI-powered fraud detection. The strategy balances security with usability while emphasizing continuous validation through penetration testing and vulnerability assessments. This comprehensive framework provides security practitioners and financial technology stakeholders with structured guidance for implementing effective protections that enhance trust in digital payment ecosystems.