Strengthening Web Application Security

Case Study : Strengthening Web Application Security for Large Fintech Enterprise

Client Profile

A major fintech enterprise with a global customer base, offering digital banking and payment gateway services. The organization handles millions of transactions daily and is subject to strict compliance standards such as PCI-DSS.

Challenge

The company wanted an external penetration test of its flagship customer-facing application, API gateway, and cloud infrastructure, aiming to identify any hidden weaknesses that could be exploited by sophisticated attackers.

Cressel's Approach

Cressel’s Red Team initiated a multi-layered penetration test using a combination of manual exploitation techniques and automated tools. The engagement involved reconnaissance, API fuzzing, web application testing, and cloud

Key Findings

While no immediate breach was reported internally, Cressel’s team discovered a set of critical vulnerabilities that could have been leveraged to escalate privileges and exfiltrate sensitive financial data.

Impact and Outcome

Cressel delivered a detailed risk-based report and worked directly with the client’s internal security team to remediate the issues. A joint workshop was held to enhance their DevSecOps practices and implement continuous monitoring around

Results

Closed multiple high-risk gaps before public exploitation

Improved visibility across internal APIs and cloud assets

Integrated penetration testing into regular CI/CD cycles