Why the OWASP API Security Top 10 Matters in API Risk Management?

Effective API security management starts with visibility, risk prioritization, and continuous testing: the OWASP 2019 & 2023 API Security Top 10 provides the baseline for all three. As APIs face increased exposure and threat, traditional security controls fail to catch modern risks like broken object-level authorization (BOLA), excessive data exposure, or improper inventory management. OWASP’s Top 10 doesn’t just highlight these critical API-specific vulnerabilities, but it also shapes how security teams structure testing, governance, and remediation workflows across the API lifecycle. 
In this blog, we’ll break down why the OWASP API Top 10 is crucial for API security management in 2025 and how security tools like APIFuzzer help you address these vulnerabilities before attackers do. 

• What Is the OWASP API Security Top 10? 
   

The OWASP API Security Top 10 is a community-curated list of the most critical security risks to APIs. Updated in 2023, the list reflects real-world breach patterns and the evolving threat landscape. It includes: 
 

1. Broken Object Level Authorization (BOLA) 
   Occurs when users can access objects (like data or resources) they shouldn't - often by manipulating object IDs. This is one of the most exploited API vulnerabilities today. 

2. Broken Authentication 
   Weak or improperly implemented authentication mechanisms that allow attackers to impersonate users or access systems without valid credentials. 

3. Broken Object Property Level Authorization (BOPLA) 
   Even if users are authorized to access an object, they shouldn't have visibility or control over all its properties. APIs often expose too much by default. 

4. Unrestricted Resource Consumption 
   APIs that don’t enforce rate limiting or usage quotas can be abused to exhaust server resources, leading to denial-of-service (DoS) attacks or degraded performance. 

5. Broken Function Level Authorization 
   A logic flaw where users can execute privileged functions (like account management or admin actions) without proper role-based checks. 

6. Unrestricted Access to Sensitive Business Flows 
   APIs that expose sensitive workflows (e.g., checkout, credit approvals) without context-aware controls, enabling attackers to manipulate high-risk processes. 

7. Server-Side Request Forgery (SSRF) 
   APIs that fetch URLs or resources based on user input can be tricked into making internal network calls, exposing private infrastructure. 

8. Security Misconfiguration 
   Common issues like overly permissive CORS, verbose error messages, or default credentials can expose dangerous attack vectors in production APIs. 

9. Improper Inventory Management 
   Shadow APIs, outdated versions, or undocumented endpoints are often left unmonitored, becoming soft targets for attackers. 

10. Unsafe Consumption of APIs 
    Trusting third-party APIs blindly without validating or sanitizing data can lead to data poisoning, logic manipulation, or injection risks. 

 Each item maps to vulnerabilities that can lead to data leaks, privilege escalation, or complete system compromise, especially when APIs are loosely tested or improperly monitored. 
 

• Why It’s Crucial in Modern API Security Management? 
   

With the shift to microservices, API-first development, and cloud-native applications, your APIs are your attack surface. The OWASP API Top 10 2019 & 2023 offers a strategic lens for: 

• Risk Prioritization 
  Instead of chasing every potential CVE, focus on the most impactful, frequently exploited API weaknesses. It is important to identify the impact the API Vulnerability would have on the overall application and the ease of accessing the same. 

• Secure Design Guidance 
  Helps developers architect APIs with built-in protections for access control, rate limiting, input validation, and more. 

• Security Testing Baseline 
  Provides a common standard for penetration testers, auditors, and AppSec teams to evaluate API posture. 

• Compliance Alignment 
  Increasingly referenced in compliance mandates and vendor risk assessments as APIs become integral to digital supply chains. 

• What Are the Limitations of Traditional API Testing Approaches? 

Most static code analysers and legacy application security testing software weren’t designed with modern APIs kept in mind. They often elude: 

• Hidden authorization flaws like BOLA  

• Context-aware logic issues in business flows 

• Issues with endpoint discovery or inventory drift 

• Inability to Handle Complex Authentication & Authorization 

• Inefficient or Incomplete Input Fuzzing 

• Inability to Discover Hidden or Non-Public Endpoints 

• Lack of API-Specific Understanding 

• How APIFuzzer Helps You Catch What Others Miss? 

APIFuzzer brings OWASP API Top 10 2019 and 2023 security guidance to life through mutation-based fuzzing and context-aware testing. It doesn't just scan for known issues- it dynamically uncovers silent vulnerabilities like verbose error responses, mismatched HTTP status code, or exposure of sensitive information within error messages or logs, that align with OWASP API security risk categories. It supports continuous testing of key OWASP threats, 

including: 

• Broken Object Level Authorization (BOLA) 

• Broken Function Level Authorization (BFLA) 

• Unrestricted Resource Consumption 

• Broken Object Property Level Authorization 

• Improper Inventory Management (e.g., shadow APIs) 

• Sensitive data exposure 

• Security misconfigurations 

• Injection Attacks and more 
   

With support for Remote Procedure Call protocols JSONRPC and XMLRPC, and API architectural paradigms REST, SOAP and GraphQL. APIFuzzer integrates directly into your CI/CD workflow and works alongside tools like JIRA, Eclipse and ZAP. It also helps discover undocumented endpoints through API-SBOM visibility: critical for tackling OWASP’s “Improper Inventory Management.” 

By allowing custom payload uploads, clientless deployment, and automated testing across environments, APIFuzzer equips security and development teams to go beyond checklist-based compliance and move toward proactive, continuous API protection. 

Whether you’re building APIs for finance, healthcare, mobility, or SaaS - APIFuzzer helps ensure your APIs are tested against real-world threats defined by OWASP, not just theoretical vulnerabilities.