Client Profile
A leading fintech company providing digital payment solutions relied heavily on its Application Programming Interface (API) ecosystem for seamless integration with banks, third-party vendors, and mobile applications. Given the sensitive nature of financial transactions, ensuring API security was critical to protect against cyber threats and regulatory non-compliance.
Challenges Faced
Before undergoing API Penetration Testing, the company identified several security concerns:
- Insecure authentication and authorization mechanisms, increasing the risk of account takeovers.
- Excessive data exposure, potentially leaking sensitive user and financial information.
- Broken object-level authorization (BOLA), allowing attackers to access or modify data they shouldn’t.
- Rate-limiting and denial-of-service (DoS) vulnerabilities, making APIs susceptible to abuse.
- Injection vulnerabilities (SQLi, XML External Entity (XXE), and Server-Side Request Forgery (SSRF)), which could compromise backend systems.
- Compliance concerns with OWASP API Security Top 10, PCI DSS, GDPR, and ISO 27001.
Our Approach
To enhance API security, we conducted a comprehensive API Penetration Testing engagement, identifying vulnerabilities and providing remediation strategies.
Scoping & Threat Modeling
We worked with the client to define:
- Scope of testing, including RESTful APIs, GraphQL endpoints, SOAP services, and third-party integrations.
- Threat models specific to APIs, such as Broken Access Control, Injection Attacks, and Business Logic Flaws.
- Testing methodologies, including Black Box, Gray Box, and White Box testing.
Security Testing Execution
Using industry-standard frameworks like OWASP API Security Top 10, NIST 800-53, and MITRE ATT&CK, we conducted rigorous API penetration testing, covering:
- Authentication & Authorization Testing – Assessing OAuth 2.0, JWT security, API keys, and token expiration policies.
- Broken Object-Level Authorization (BOLA) Testing – Identifying vulnerabilities where users can access other users’ data without proper authorization.
- Broken User Authentication Testing – Evaluating API login mechanisms, multi-factor authentication (MFA), and brute-force attack resilience.
- Excessive Data Exposure Testing – Detecting APIs that leak sensitive information due to improper response handling.
- Rate Limiting & DoS Testing – Identifying endpoints vulnerable to brute-force attacks and denial-of-service (DoS) threats.
- Injection Attacks Testing – Testing for SQL Injection (SQLi), Command Injection, XML External Entity (XXE), and Server-Side Request Forgery (SSRF).
- API Endpoint Security Testing – Assessing CORS misconfigurations, unrestricted file uploads, and improper logging practices.
- Business Logic Flaws Testing – Identifying API behaviors that could be manipulated to bypass security controls.
Findings & Risk Assessment
After completing the penetration test, we provided a detailed security report, including:
- Critical, High, Medium, and Low-risk vulnerabilities, with business impact analysis.
- Proof-of-Concept (PoC) exploits, demonstrating how attackers could exploit vulnerabilities.
- A prioritized remediation roadmap, helping the company fix vulnerabilities efficiently.
Remediation Support & Secure API Development Best Practices
To ensure the API ecosystem remained secure, we provided:
- Secure coding guidelines to prevent BOLA, BFLA, and injection attacks.
- Improved authentication mechanisms, including OAuth 2.0 hardening, token validation, and API key management.
- Implementation of rate limiting and throttling, preventing API abuse and DoS attacks.
- Enhanced logging and monitoring, enabling real-time API security event detection.
- Re-testing of critical vulnerabilities, ensuring proper remediation.
Compliance & Continuous Security
After implementing security fixes, the company achieved:
- Stronger API security posture, eliminating critical security flaws.
- Compliance readiness for PCI DSS, GDPR, ISO 27001, and OWASP standards.
- Secure API integrations, reducing the risk of data breaches and unauthorized access.
- Implementation of continuous security monitoring, ensuring long-term protection.
Results Achieved
Within six weeks, the company successfully:
- Eliminated critical security vulnerabilities, including BOLA, SQLi, and token misconfigurations.
- Hardened authentication and authorization mechanisms, preventing unauthorized access.
- Implemented best practices for API security, reducing attack surfaces.
- Adopted a Secure API Development Lifecycle (API-SDLC), ensuring long-term security improvements.
Conclusion
By leveraging our API Penetration Testing expertise, we helped the fintech company proactively identify vulnerabilities, enhance security controls, and achieve compliance with industry regulations. Our structured approach, from threat modeling to remediation, ensured the API ecosystem remained resilient against cyber threats.
Need API Penetration Testing?
If you’re looking to secure your APIs against security threats and compliance risks, reach out to us today for a customized API penetration testing engagement.
COE Security LLC
COE Security is a leading cybersecurity services provider, offering comprehensive solutions to address the evolving threat landscape. We have a proven track record of helping organizations of all sizes mitigate risks, strengthen defenses, and recover from cyberattacks. Our team of experienced cybersecurity professionals possesses deep expertise in the latest technologies and best practices, enabling us to deliver tailored solutions that meet your unique security needs.
We offer a wide range of services, including:
Security Services
- Application Penetration Testing – Assessing the security of applications by simulating real-world attacks to identify vulnerabilities.
- Mobile Application Penetration Testing – Evaluating the security of mobile applications on Android and iOS to detect potential risks.
- Web Application Penetration Testing – Identifying and mitigating security flaws in web applications to prevent cyber threats.
- Thick Client Penetration Testing – Testing desktop applications to uncover security gaps that could be exploited by attackers.
- API Penetration Testing – Ensuring the security of APIs by detecting vulnerabilities that could lead to unauthorized access or data leaks.
- Network Penetration Testing – Evaluating network infrastructure for weaknesses that hackers could exploit to gain access.
- Hardware Penetration Testing – Identifying security flaws in hardware components that could compromise overall system security.
- Operational Technology Security Testing – Protecting critical industrial control systems from cyber threats and potential disruptions.
- Cloud Penetration Testing – Assessing cloud environments for vulnerabilities to ensure the security of cloud-based assets.
- AWS Penetration Testing – Conducting security assessments for AWS environments to detect and mitigate risks.
- GCP Penetration Testing – Evaluating security risks in Google Cloud Platform (GCP) to safeguard cloud assets and infrastructure.
- Azure Penetration Testing – Identifying vulnerabilities in Microsoft Azure cloud environments to prevent unauthorized access.
- Alibaba Penetration Testing – Ensuring the security of Alibaba Cloud infrastructures against evolving cyber threats.
- AI & LLM Penetration Testing – Assessing security risks in artificial intelligence (AI) and large language model (LLM) applications.
- Red Teaming – Simulating advanced attack scenarios to test an organization’s cyber resilience against real-world threats.
- Social Engineering Service – Identifying human-related security weaknesses through phishing, impersonation, and other social engineering tactics.
- Product Penetration Testing – Evaluating security vulnerabilities in software and hardware products before deployment.
- IoT Security – Securing connected devices to prevent them from becoming entry points for attackers.
- DevSecOps & Secure Software Development – Embedding security into the software development lifecycle.
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