API Security
API security addresses the unique vulnerabilities that arise when applications expose functionality through programmatic interfaces. As organizations shift to API-first architectures, microservices, and third-party integrations, APIs have become the primary attack surface for modern applications. The OWASP API Security Top 10 identifies critical risks including Broken Object Level Authorization (BOLA), mass assignment, excessive data exposure, and lack of rate limiting. APIs often inadvertently expose more data than their UI counterparts, accept parameters that bypass frontend validation, and may lack the authentication and authorization checks that browser-based interfaces enforce. REST, GraphQL, gRPC, and WebSocket APIs each present distinct security challenges. Effective API security requires authentication hardening, input validation, output filtering, rate limiting, proper error handling, and comprehensive logging across every endpoint.
| Date Added | Link | Excerpt |
|---|---|---|
| 2026-04-22 NEW 2026 | A Deep Dive on the Most Critical API Vulnerability: BOLA | A Deep Dive on the Most Critical API Vulnerability: BOLA |
| 2026-04-22 NEW 2026 | What Is Broken Object Property Level Authorization? | What Is Broken Object Property Level Authorization? |
| 2026-04-22 NEW 2026 | What Is Broken Object Level Authorization? | What Is Broken Object Level Authorization? |
| 2026-04-22 NEW 2026 | This Is How I Hacked an API Using Mass Assignment Vulnerability | This Is How I Hacked an API Using Mass Assignment Vulnerability |
| 2026-04-22 NEW 2026 | CVE-2026-34839: CORS Vulnerability in Glances REST API | CVE-2026-34839: CORS Vulnerability in Glances REST API |
| 2026-04-22 NEW 2026 | API ThreatStats Report 2026 | API ThreatStats Report 2026 |
| 2026-04-22 NEW 2026 | VAmPI: Vulnerable REST API with OWASP Top 10 Vulnerabilities | VAmPI: Vulnerable REST API with OWASP Top 10 Vulnerabilities |
| 2026-04-22 NEW 2026 | API4:2023 Unrestricted Resource Consumption | API4:2023 Unrestricted Resource Consumption |
| 2026-04-22 NEW 2026 | 1H 2026 State of AI and API Security Report (Salt) | 1H 2026 State of AI and API Security Report (Salt) |
| 2026-04-22 NEW 2026 | PortSwigger Lab: Exploiting a Mass Assignment Vulnerability | PortSwigger Lab: Exploiting a Mass Assignment Vulnerability |
| 2026-04-19 NEW 2026 | BOLA API Attack & Prevention — StackHawk | BOLA API Attack & Prevention — StackHawk |
| 2026-04-19 NEW 2026 | Broken Object-Level Authorization (BOLA): What It Is and How to Prevent It | Broken Object-Level Authorization (BOLA): What It Is and How to Prevent It |
| 2026-04-19 NEW 2026 | OWASP Top 10 API Security Risks and How to Mitigate Them — Pynt | OWASP Top 10 API Security Risks and How to Mitigate Them — Pynt |
| 2026-04-19 NEW 2026 | OWASP Top 10 2025: Latest Changes and Enhancements | OWASP Top 10 2025: Latest Changes and Enhancements |
| 2026-04-19 NEW 2026 | OWASP API Security Top 10 Vulnerabilities — 2025 | OWASP API Security Top 10 Vulnerabilities — 2025 |
| 2026-04-16 NEW 2026 | MCP Access Control: OPA vs Cedar - Natoma | MCP Access Control: OPA vs Cedar - Natoma |
| 2026-04-16 NEW 2026 | Stateful REST API Fuzzing with RESTler | Stateful REST API Fuzzing with RESTler |
| 2026-04-16 NEW 2026 | Inside Modern API Attacks: 2026 API ThreatStats Report - Wallarm | Inside Modern API Attacks: 2026 API ThreatStats Report - Wallarm |
| 2026-04-16 NEW 2026 | OWASP API Security Testing Framework | OWASP API Security Testing Framework |
| 2026-04-16 NEW 2026 | Kong API Gateway Misconfigurations Case Study - Trend Micro | Kong API Gateway Misconfigurations Case Study - Trend Micro |
| 2026-04-16 NEW 2026 | API Security Testing: Tools and Techniques - API7.ai | API Security Testing: Tools and Techniques - API7.ai |
| 2026-04-16 NEW 2026 | BOLA and BFLA: The API Vulnerabilities That Silently Expose Data | BOLA and BFLA: The API Vulnerabilities That Silently Expose Data |
| 2026-04-16 NEW 2026 | API Penetration Testing: Complete Guide | API Penetration Testing: Complete Guide |
| 2026-04-16 NEW 2026 | How to Protect APIs from OWASP Authorization Risks: BOLA, BOPLA and BFLA - 42Crunch | How to Protect APIs from OWASP Authorization Risks: BOLA, BOPLA and BFLA - 42Crunch |
| 2026-04-16 NEW 2026 | Securing the Gates: Mastering BOLA and BFLA in API Security | Securing the Gates: Mastering BOLA and BFLA in API Security |
| 2026-04-11 2026 | Exploiting API4: 8 Real-World Unrestricted Resource Consumption Attack Scenarios | Exploiting API4: 8 Real-World Unrestricted Resource Consumption Attack Scenarios |
| 2026-04-11 2026 | Exploiting Server-Side Request Forgery in an API | Exploiting Server-Side Request Forgery in an API |
| 2026-04-11 2026 | API Versioning Vulnerabilities: Deprecated Endpoints Still Accepting Requests | API Versioning Vulnerabilities: Deprecated Endpoints Still Accepting Requests |
| 2026-04-11 2026 | Exploiting JWT Vulnerabilities: Advanced Exploitation Guide | Exploiting JWT Vulnerabilities: Advanced Exploitation Guide |
| 2026-04-11 2026 | openapi-fuzzer: Black-box Fuzzer for OpenAPI Specifications | openapi-fuzzer: Black-box Fuzzer for OpenAPI Specifications |
| 2026-04-11 2026 | CATS: REST API Fuzzer and Negative Testing Tool | CATS: REST API Fuzzer and Negative Testing Tool |
| 2026-04-11 2026 | RESTler: Stateful REST API Fuzzing Tool | RESTler: Stateful REST API Fuzzing Tool |
| 2026-04-11 2026 | BFLA: Broken Function Level Authorization | BFLA: Broken Function Level Authorization |
| 2026-04-11 2026 | API Gateway Authorizers: Vulnerable By Design | API Gateway Authorizers: Vulnerable By Design |
| 2026-04-11 2026 | HTTP Request Smuggling in API Gateways | HTTP Request Smuggling in API Gateways |
| 2026-04-11 2026 | Kong API Gateway Misconfigurations: A Security Case Study | Kong API Gateway Misconfigurations: A Security Case Study |
| 2026-04-11 2026 | Swagger-EZ: Pentesting APIs Using OpenAPI Definitions | Swagger-EZ: Pentesting APIs Using OpenAPI Definitions |
| 2026-04-11 2026 | APIDetector: Scan for Exposed Swagger Endpoints | APIDetector: Scan for Exposed Swagger Endpoints |
| 2026-04-11 2026 | Autoswagger: Automated Discovery and Testing of OpenAPI and Swagger Endpoints | Autoswagger: Automated Discovery and Testing of OpenAPI and Swagger Endpoints |
| 2026-04-11 2026 | Swagger Jacker: Auditing OpenAPI Definition Files | Swagger Jacker: Auditing OpenAPI Definition Files |
| 2026-04-11 2026 | PayloadsAllTheThings: API Key Leaks | PayloadsAllTheThings: API Key Leaks |
| 2026-04-11 2026 | State of Secrets: 28 Million Credentials Leaked on GitHub in 2025 | State of Secrets: 28 Million Credentials Leaked on GitHub in 2025 |
| 2026-04-11 2026 | Bypassing Rate Limits: All Known Techniques | Bypassing Rate Limits: All Known Techniques |
| 2026-04-11 2026 | Rate Limit Bypass - HackTricks | Rate Limit Bypass - HackTricks |
| 2026-04-11 2026 | Hacking APIs: Bypassing Rate Limiting | Hacking APIs: Bypassing Rate Limiting |
| 2026-04-11 2026 | What is Mass Assignment? Attacks and Security Tips | What is Mass Assignment? Attacks and Security Tips |
| 2026-04-11 2026 | API Security 101: Mass Assignment and Exploitation in the Wild | API Security 101: Mass Assignment and Exploitation in the Wild |
| 2026-04-11 2026 | What is BOLA? 3-digit bounty from Topcoder | What is BOLA? 3-digit bounty from Topcoder |
| 2026-04-11 2026 | API1:2023 Broken Object Level Authorization | API1:2023 Broken Object Level Authorization |
| 2026-04-11 2026 | Exposing a New BOLA Vulnerability in Grafana | Exposing a New BOLA Vulnerability in Grafana |
| 2026-04-10 2026 | API Exploitation For Bug Bounty | API Exploitation For Bug Bounty |
| 2026-04-10 2026 | API Penetration Testing Roadmap (2025) | API Penetration Testing Roadmap (2025) |
| 2026-04-10 2026 | API Security Testing Tool Checklist (2026) | API Security Testing Tool Checklist (2026) |
| 2026-04-10 2026 | GraphQL Security Best Practices: A Developer's Guide | GraphQL Security Best Practices: A Developer's Guide |
| 2026-04-10 2026 | OWASP API Security Top 10 Risks | OWASP API Security Top 10 Risks |
| 2026-04-10 2026 | API Security Reality Check: Q2 2025 API ThreatStats Report | API Security Reality Check: Q2 2025 API ThreatStats Report |
| 2026-04-10 2026 | GraphQL Security Testing: Complete Guide | GraphQL Security Testing: Complete Guide |
| 2026-04-10 2026 | Common API Security Vulnerabilities & Solutions (2026 Guide) | Common API Security Vulnerabilities & Solutions (2026 Guide) |
| 2026-04-10 2026 | Common Attacks on REST APIs and GraphQL APIs | Common Attacks on REST APIs and GraphQL APIs |
| 2026-04-10 2026 | GraphQL API Security: Common Vulnerabilities and Exploits | GraphQL API Security: Common Vulnerabilities and Exploits |
| 2026-04-10 2026 | Introduction - OWASP Top 10:2025 | Introduction - OWASP Top 10:2025 |
| 2026-04-10 2026 | OWASP Top 10:2025 | OWASP Top 10:2025 |
| 2026-04-10 2026 | API Security Risks: The 10 Most Exploited in 2026 | API Security Risks: The 10 Most Exploited in 2026 |
| 2026-04-10 2026 | What Are the OWASP Top 10 API Security Risks? - Akamai | What Are the OWASP Top 10 API Security Risks? - Akamai |
| 2026-04-10 2026 | OWASP API Security Top 10 (2025) Guide with Tests | OWASP API Security Top 10 (2025) Guide with Tests |
| 2026-04-10 2026 | OWASP Top 10 2025: What's Changed and Why | OWASP Top 10 2025: What's Changed and Why |
| 2026-04-10 2026 | Top 10 OWASP API Security in 2026 | Top 10 OWASP API Security in 2026 |
| 2026-04-10 2026 | OWASP Top Ten 2025: Key Security Risks for APIs | OWASP Top Ten 2025: Key Security Risks for APIs |
| 2026-04-10 2026 | OWASP API Security: Top 10 Risks & Remedies for 2026 | OWASP API Security: Top 10 Risks & Remedies for 2026 |
| 2026-04-06 2026 | Protecting Payment, Cart, and Login Endpoints at the Edge | Protecting Payment, Cart, and Login Endpoints at the Edge |
| 2026-04-06 2026 | Open Banking API Security: The Complete Guide in 2026 | Open Banking API Security: The Complete Guide in 2026 |
| 2026-04-06 2026 | Enhancing REST API Fuzzing with Access Policy Violation Detection | Enhancing REST API Fuzzing with Access Policy Violation Detection |
| 2026-04-06 2026 | 6 Ways to Protect Your Spring Boot APIs from Common Attacks | 6 Ways to Protect Your Spring Boot APIs from Common Attacks |
| 2026-04-06 2026 | 7 Identity and API Security Tools Modern SaaS Teams Should Evaluate in 2026 | 7 Identity and API Security Tools Modern SaaS Teams Should Evaluate in 2026 |
| 2026-04-03 2026 | InQL - GraphQL Scanner | PortSwigger BApp Store | InQL - GraphQL Scanner | PortSwigger BApp Store |
| 2026-04-03 2026 | OWASP API Security Top 10 Explained | Salt Security | OWASP API Security Top 10 Explained | Salt Security |
| 2026-04-03 2026 | How To Prepare For An API Penetration Test | How To Prepare For An API Penetration Test |
| 2026-04-03 2026 | Awesome GraphQL Security - Curated List of Resources | Awesome GraphQL Security - Curated List of Resources |
| 2026-04-03 2026 | API Testing with Burp Suite: A Practical Guide | API Testing with Burp Suite: A Practical Guide |
| 2026-04-03 2026 | Top 6 API Pentesting Tools | Cobalt | Top 6 API Pentesting Tools | Cobalt |
| 2026-04-03 2026 | API Attack Awareness: BOLA - Why It Tops the OWASP API Top 10 | API Attack Awareness: BOLA - Why It Tops the OWASP API Top 10 |
| 2026-04-03 2026 | GraphQL API Vulnerabilities | Web Security Academy | GraphQL API Vulnerabilities | Web Security Academy |
| 2026-04-03 2026 | API Testing | Web Security Academy | API Testing | Web Security Academy |
| 2026-04-03 2026 | OWASP API Security Top 10 | OWASP API Security Top 10 |
| 2026-04-03 2026 | OWASP API Security Project | OWASP Foundation | The API Security project focuses on strategies and solutions to understand and mitigate the unique vulnerabilities and security risks of Application Programming Interfaces (APIs) |
Frequently Asked Questions
- What is the OWASP API Security Top 10?
- The OWASP API Security Top 10 is a list of the most critical API security risks, including Broken Object Level Authorization (BOLA), Broken Authentication, Broken Object Property Level Authorization, Unrestricted Resource Consumption, Broken Function Level Authorization, Server Side Request Forgery, Security Misconfiguration, and Lack of Protection from Automated Threats.
- Why are APIs harder to secure than web applications?
- APIs often expose more data and functionality than web UIs, accept complex input formats, lack the natural access controls of a browser interface, and are harder to monitor. They also tend to grow organically, creating shadow APIs that bypass security controls, and their machine-to-machine nature makes abuse detection more difficult.
- What tools are used for API security testing?
- Common tools include Burp Suite with API-focused extensions, Postman for manual testing, OWASP ZAP for automated scanning, Akto for API inventory and testing, and custom scripts for fuzzing API parameters. For GraphQL APIs, InQL and graphql-cop are essential. API specification files (OpenAPI/Swagger) are valuable for understanding and testing the full attack surface.
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