Penetration Testing for Fintech Companies in the UK

Penetration testing for fintech companies in the UK

Fintech companies occupy a uniquely challenging position in the UK cyber security landscape. They handle sensitive financial data, operate under FCA regulation, process payments, and manage user funds — making them both high-value targets and subject to significant regulatory scrutiny around security.

Why fintech companies are high-priority targets

The combination of financial data, payment functionality, and user funds makes fintech platforms significantly more valuable to attackers than most other web applications. A vulnerability that allows account takeover does not just expose data — it potentially allows theft of user funds. A vulnerability in a payment flow can enable fraudulent transactions. A breach of financial records creates ICO liability and potentially FCA regulatory consequences simultaneously.

Fintech companies also tend to move fast. Startup culture, rapid iteration, and aggressive growth timelines create pressure to ship features quickly — and security testing is often the thing that gets deprioritised when deadlines are tight. The result is that vulnerabilities introduced early in development can persist into production for months or years.

The regulatory framework

FCA-regulated firms have explicit obligations around operational resilience and cyber security. The FCA's operational resilience requirements, which came into full force in 2022, require firms to identify important business services, set impact tolerances for disruption, and test their ability to remain within those tolerances.

The FCA has made clear through supervisory work and Dear CEO letters that it expects firms to maintain robust cyber security controls proportionate to their risk profile. Firms that experience security incidents and cannot demonstrate adequate security testing face both regulatory consequences and reputational damage.

Under UK GDPR, fintech companies processing financial data have the same obligations as any other data controller — but the sensitivity and volume of data they handle means the ICO treats breaches seriously.

Common vulnerabilities in fintech applications

Authentication and authorisation weaknesses are particularly impactful in fintech contexts. IDOR vulnerabilities that allow one user to access another's account or transaction history are common findings. JWT vulnerabilities that allow authentication bypass can give attackers access to financial functionality without credentials.

API security issues are prevalent. Fintech platforms typically expose extensive APIs — for mobile apps, partner integrations, and internal services. APIs that lack proper authentication, expose excessive data, or have rate limiting issues create significant attack surface.

Business logic vulnerabilities — flaws in how financial calculations, transaction limits, or payment flows are implemented — can allow manipulation of financial outcomes in ways that automated scanners sometimes miss but that Yrzo AI's checks are designed to probe.

Payment flow vulnerabilities, including issues with how payment confirmations are validated and how transaction states are managed, can enable fraudulent transactions in applications that are not carefully implemented.

What penetration testing covers for a fintech company

A security assessment for a fintech platform tests authentication and session management, API security across all externally accessible endpoints, authorisation controls ensuring users can only access their own data, payment flow integrity, and common web application vulnerabilities including injection attacks and XSS.

Yrzo AI runs 44 automated security checks covering the web application attack surface comprehensively. Starting at £399 per scan, it provides a documented baseline security assessment suitable for internal security programmes and as evidence of due diligence for regulatory purposes.