Choose an API security testing tool by running it against your own APIs and checking what it finds against the OWASP API Security Top 10. The criteria that separate tools are API discovery, authenticated testing, handling of authorization logic, safe scanning controls and fit with your pipeline. This is a how-to-choose guide and does not rank products.
No one tool covers every API risk, so the aim is a clear picture of what each tool can and cannot see. Start with what you are defending against.
What risks are you testing for?
The OWASP API Security Top 10 (2023 edition) lists the common ones:
- API1 Broken Object Level Authorization
- API2 Broken Authentication
- API3 Broken Object Property Level Authorization
- API4 Unrestricted Resource Consumption
- API5 Broken Function Level Authorization
- API6 Unrestricted Access to Sensitive Business Flows
- API7 Server Side Request Forgery
- API8 Security Misconfiguration
- API9 Improper Inventory Management
- API10 Unsafe Consumption of APIs
Notice how many are about authorization and business logic rather than injection strings. A tool that only sends malformed input will miss API1, API3 and API5, because those need to know who the caller is and what they should see.
Which criteria matter most?
1. Discovery and inventory. API9 is about not knowing what you expose. Ask how the tool learns your endpoints: from an OpenAPI file, from traffic, from source code, or by crawling. Test it with an endpoint you deliberately left out of your spec.
2. Authenticated and multi-user testing. To find broken object level authorization, a tool must act as two different users and try to read each other's objects. Ask whether it supports multiple credentials, token refresh and your auth scheme.
3. Logic and business flow coverage. API6 is hard to automate. Ask the vendor what they test for it and what they leave to manual review. A straight answer is a good sign.
4. Safety controls. A scanner that sends requests can break things. Look for scope limits, rate limits, a non-destructive default mode and an audit trail of requests. These matter for production-like targets.
5. Static, dynamic or both. Static analysis reads source and sees code paths. Dynamic testing sees the running behavior and configuration. They find different things, and the OWASP Web Security Testing Guide is a good reference for the dynamic side. Ask how the tool links a runtime finding to the code that caused it.
6. Pipeline fit. Check CI support, output formats such as SARIF, how it fails a build, and how long a scan takes. A scan that takes six hours will run once a month.
7. Findings quality. Ask for evidence per finding: request, response, and why it is exploitable. Count false positives in your trial.
How do you run a fair trial?
Build a small test API with known flaws: one object-level authorization hole, one missing function-level check, one undocumented endpoint, and one verbose error. Run each candidate against it and against one real internal API. Score what it found, what it missed, and how long triage took. Do this in a staging environment you own, with permission, and never against a system you do not control.
What are the limits?
Automated tools are weakest at authorization and business logic, the categories that dominate the OWASP list. Expect to pair a tool with manual testing and code review for critical flows. Also, a tool that works well on REST may handle GraphQL, gRPC or WebSocket APIs differently, so test your actual protocols.
Safeguard's own documentation describes SAST and DAST as rolling out, with detection depth expanding over time and safety controls such as verified targets and scope limits in place. Judge it with the same trial plan you use for anyone else.
What to do
- List your APIs and protocols, including the ones not in your spec.
- Write a test API with known authorization flaws.
- Score each tool on the seven criteria with evidence.
- Test authenticated, multi-user scenarios first.
- Check safety controls before pointing a tool at anything shared.
- Plan manual testing for sensitive business flows.
Quick check
Can a scanner find broken object level authorization?
Only if it can authenticate as more than one user and compare what each can access. Many tools cannot, so test this directly.
Is one API security tool enough?
Usually not. Combine automated testing with code review and manual checks for authorization and business logic.
Sources
- OWASP API Security Top 10, 2023
- OWASP Web Security Testing Guide
- Safeguard application security testing
Last reviewed: 18 October 2026.
