In the world of web and digital interactions, APIs serve as critical gateways, enabling seamless communication and functionality across applications. However, without robust security measures, they can inadvertently become the weakest link in an organization’s cybersecurity chain. This blog sheds light on a recent discovery of flawed API access controls, showcasing how BeVigil’s advanced security capabilities can uncover and mitigate such vulnerabilities.

Misconfigured APIs and Flawed Access Controls
During an in-depth security analysis, BeVigil’s WebApp scanner uncovered a significant vulnerability in an API documentation interface. A misconfigured web application allowed unauthenticated access to sensitive internal APIs, exposing critical customer data and operational functionalities. This issue stemmed from an insecure authorization mechanism that accepted arbitrary inputs as valid credentials.
Key Issues Identified
- Exposed API Documentation: The API documentation, though intended to be inaccessible, was easily retrieved due to a flawed anti-detection mechanism.
- Weak Authorization Mechanism: Authentication controls allowed random values to bypass security checks.
- Sensitive Endpoint Exposure: Endpoints capable of fetching personal identifiable information (PII), modifying user data, and performing critical banking operations were exposed.

Unmasking Security Flaws: A Detailed Analysis
- BeVigil identified a web application with a disabled documentation page that could be bypassed due to weak security measures. Using tools like BurpSuite, it was possible to access exposed API endpoints. These endpoints enabled actions such as token generation, PAN validation, OTP management, and access to sensitive banking information, demonstrating a significant vulnerability.



- The "Customer Profile" API enables access to sensitive customer data, including profiles, transactions, and account details. Unauthorized access also allows updates to personal and transactional information, posing a major security risk.


- The "Bill Payments" API exposed sensitive biller information, including names, IDs, banking limits, and addresses, highlighting a critical data vulnerability.

BeVigil’s Security Intervention
BeVigil employed a systematic approach to identify, analyze, and recommend actionable steps to mitigate the vulnerabilities, we took the following key actions:
- Identified exposed API documentation and insecure pathways that allowed unauthorized access.
- Recommended disabling public API documentation or securing it with strict access controls.
- Strengthened access controls by advising robust authentication mechanisms like token-based authentication and input validation.
- Implemented periodic security audits to proactively detect vulnerabilities and anomalies.
- Suggested disabling unused API routes and enforcing rate-limiting to prevent abuse.
- Emphasized secure coding practices by educating development teams on best security measures.
This incident underscores the importance of a security-first approach in API management. Securing APIs is not just a technical necessity but a strategic imperative in today’s digital economy. With BeVigil’s advanced tools and methodologies, organizations can ensure their API ecosystems remain secure, fostering trust and operational excellence in an increasingly interconnected world.