In today's interconnected digital landscape, Application Programming Interfaces (APIs) have become the backbone of modern software development. APIs enable seamless communication between different software components, making it possible for applications to interact with each other and provide a richer user experience. However, the widespread use of APIs also brings along a new set of challenges – security vulnerabilities.

In this blog post, we will delve into the most common API security vulnerabilities we have identified based on our own recent internal analysis of Pynt’s vast community of users. We emphasize the pivotal role of comprehensive security assessments from as far left as possible in the SDLC, and how to achieve it.

The Growing Importance of API Security

APIs serve as the building blocks for numerous web and mobile applications, granting them access to critical data and functionality. As a result, they have become an attractive target for cybercriminals seeking to exploit vulnerabilities for various malicious purposes, such as data breaches, unauthorized access, or injecting malicious code. It is imperative for organizations to recognize these threats and address them proactively through rigorous security testing.

Brewing API confidence

Before we dive into the common API security vulnerabilities, some context of Pynt, and our users, which this analysis is based upon. Pynt is an API Security Testing solution designed to help organizations identify vulnerabilities early in the development lifecycle. Pynt's distinct advantage lies in its ability to discover these vulnerabilities right at the developer's desk, preventing them from reaching production environments where the consequences could be dire.

Pynts users include software developers and testers who use Pynt to run API security tests, and security owners who use Pynt to view and manage the entire API security posture of the organization.

Common API Security Vulnerabilities

Based on an aggregation of vulnerability reports generated by Pynt - run on real APIs in development we have found these to be the most common:

1. Injection Vulnerabilities

Injection vulnerabilities continue to plague the API landscape. These vulnerabilities occur when untrusted data is improperly handled by the application, allowing attackers to inject malicious code or commands.

Pynt's comprehensive scanning has shed light on around 300 instances of injection vulnerabilities, including command injection, SQL injection, and NoSQL injection. These vulnerabilities have the potential to trigger various adverse outcomes, from revealing information to compromising data, causing Denial of Service (DoS) incidents, or even taking control of an entire system.

Interestingly, despite not making it to the 2023 version of the OWASP API Top 10, injection vulnerabilities continue to be a significant threat—proving their ongoing relevance.

2. BOLA (Broken Object Level Authorization)

BOLA, or Broken Object Level Authorization, is another prevalent API security vulnerability. This occurs when an application fails to validate whether a user has the appropriate permissions to access or modify a resource. Attackers can exploit this weakness to gain unauthorized access to sensitive data or perform actions they shouldn't be able to.

Pynt's vigilant approach has resulted in the discovery of over 200 unique instances of BOLA (Broken Object Level Authorization) vulnerabilities. These vulnerabilities, which are a significant concern for APIs according to OWASP, have gained even more attention through a joint advisory from the NSA, ACSC, and CISA. The implications are clear: unauthorized entities gaining access to sensitive data and resources belonging to other users.

3. Missing Authentication

Authentication is the cornerstone of any secure API. However, missing authentication, where APIs lack proper user verification, is a frequent security lapse. Without authentication, unauthorized users can gain access to restricted resources, putting sensitive data at risk.

By using Pynt, organizations can identify instances of missing authentication early in the development process, ensuring that only authorized users can access their APIs.

Equipped with powerful scanning capabilities, Pynt has identified a staggering 900 cases of missing authentication. This finding underscores the importance of robust authentication verification mechanisms in preventing unauthorized access to user data and unauthorized actions performed on their behalf.

4. Flawed JWT Validations

JWT (JSON Web Token) validations are a critical aspect of ensuring the security and integrity of JWTs, which are widely used for authentication and authorization in web applications and APIs. JWTs are compact, self-contained tokens that carry information in a JSON format and are signed or optionally encrypted. When validating JWTs, various checks are performed to ensure their authenticity, integrity, and validity.

Further showcasing Pynt's effectiveness, the scanning process has brought to light approximately 140 instances of flawed JWT (JSON Web Token) validations. These vulnerabilities could potentially lead to unauthorized access to user data and the execution of actions on their behalf.

Empowering Swift Developer Action

Most importantly, all these vulnerabilities were pinpointed right at the developer's desk—enabling swift resolution well before they could impact production environments. This proactive approach aligns with Pynt's commitment to encouraging secure development practices and thwarting potential security breaches.

Early detection and remediation benefits

1. Cost Savings: Fixing vulnerabilities in the development phase is significantly more cost-effective than addressing them in production, where the consequences can be severe.

2. Time Efficiency: Pynt accelerates the vulnerability identification process, allowing development teams to streamline security assessments and meet project deadlines.

3. Enhanced Reputation: Proactively addressing vulnerabilities showcases a commitment to security and can enhance an organization's reputation among customers and partners.

4. Compliance: Many regulatory frameworks require organizations to conduct thorough security assessments. Pynt helps organizations remain compliant by identifying and addressing vulnerabilities in line with industry standards.


As the reliance on APIs continues to grow, so does the importance of ensuring their security. Common vulnerabilities such as injection vulnerabilities, BOLA, missing authentication, and broken authentication pose significant risks to organizations. Pynt’s API Security solution, offers a proactive way of identifying and addressing these vulnerabilities aligned with the shift-left approach and preventing them from reaching production environments.

In today's threat landscape, it is no longer sufficient to rely solely on post-production security assessments. Organizations must embrace proactive security testing to protect their APIs and the valuable data they handle. Pynt is your partner in this journey, helping you secure your APIs from the ground up and from left to right.