API security testing that runs with every regression
Test for BOLA, IDOR, auth bypass, and injection in the same suite as your functional tests. Qodex writes the attack scenarios, replays them on schedule, and refuses to relax a failing security check.
4.9 / 5 from 60 reviews on G2Security testing is one module of Qodex, the agentic AI QA platform: the same autonomous agent covers UI testing, API testing, and PR review.
GET /api/v1/invoices/8412 as user B returned 200, expected 403. Cross-user read succeeded; filed with severity, repro steps, and captured evidence.
GET /api/v1/invoices/8412 Authorization: Bearer <user_b>
{ "invoice_id": 8412,
"customer": "user_a@example.com",
"total": 1840.00 }See the agent attack a real API
Claims about AI security testing are cheap. The test is whether an agent can take a plain-English request, author an attack scenario, and produce a finding you can verify. Here is Qodex doing exactly that.
What is API security testing?
API security testing sends hostile requests at your API on purpose (foreign object IDs, tampered tokens, oversized payloads, injection strings) and proves the API refuses every one. It is a form of dynamic application security testing (DAST): it exercises the running API rather than scanning source code, and it never stops at the happy path.
The highest-impact API vulnerabilities are authorization failures, one user reading another user's data or a regular role reaching an admin function, and they are invisible to scanners that never authenticate. Qodex writes these attack scenarios, runs them across multiple auth roles, and replays them on every release as part of the wider agentic AI QA platform, in the same suite as your functional API tests.
Chat, attack scenario, deterministic replay
An autonomous agent replaces the repetitive part of both the yearly pentest and the miss-everything-authenticated scanner with a three-step loop.
You name the target in chat
Tell the agent what to attack in plain English: audit /invoices for IDOR, sweep the API for the OWASP Top 10. No DSL, no payload library to wire up.
The agent writes an attack scenario
Using your auth profiles, it authors a structured scenario with inverted semantics: goal, ordered steps, and an assertion where a pass means the attack was blocked, plus a runnable script you can read.
Replay is deterministic, and free
Once saved, the scenario is plain code: same payloads, same assertions, no model in the loop. Running the full OWASP suite on every deploy costs nothing extra in LLM spend.
A human reviews findings; the agent files them, classifying each replay failure as a real bug, a stale test the API outgrew, or an environment issue.
The six checks that catch real breaches
A useful security test proves the API refuses what it should refuse, including the authorization checks that require logging in as more than one user, which is exactly where the worst bugs hide.
| Object-level authorization | Whether user B can read or mutate user A's objects by changing an ID. This is BOLA/IDOR, the number one API risk, and it is invisible to scanners that never authenticate as two users. |
|---|---|
| Authentication strength | Whether protected endpoints reject expired, missing, tampered, and cross-environment tokens instead of trusting anything that looks like a JWT. |
| Function-level authorization | Whether a regular role can reach admin or internal endpoints, including verb switching like flipping a GET to a DELETE on the same route. |
| Input validation and injection | Whether injection strings, malformed bodies, and oversized payloads come back inert and structured rather than as a 500, a stack trace, or executed input. |
| Data exposure and misconfiguration | Whether responses leak fields a role should not see, whether errors are verbose, whether CORS is permissive, and whether debug endpoints are reachable. |
| Resource and flow abuse | Whether rate limits, payload caps, and state checks hold when sensitive flows are driven at machine speed and out of order. |
The OWASP API Security Top 10
The OWASP API Security Top 10 (2023 edition) is the standard map of how APIs actually get breached. Here is each risk, and how the agent tests for it against your real endpoint inventory, so coverage tracks what your API exposes, not a generic checklist.
| Risk | Name | How an agent tests it |
|---|---|---|
| API1:2023 | Broken Object Level Authorization (BOLA) | Request objects owned by user A while authenticated as user B, across every object-bearing endpoint. Pass means the API returns 403/404; a 200 with foreign data files a finding. |
| API2:2023 | Broken Authentication | Probe token handling: expired tokens, missing tokens, tampered signatures, tokens from other environments. Verify protected endpoints reject every variant. |
| API3:2023 | Broken Object Property Level Authorization | Send writes containing fields the role should not control (role, is_admin, price) and read responses for fields it should not see. Pass means extra properties are ignored or rejected. |
| API4:2023 | Unrestricted Resource Consumption | Request oversized page sizes, deep pagination, and repeated expensive operations; check for rate limits, payload caps, and bounded responses instead of timeouts. |
| API5:2023 | Broken Function Level Authorization | Call admin and internal endpoints with non-admin credentials, including verb switching (GET to DELETE) on the same route. Pass means the role boundary holds per function. |
| API6:2023 | Unrestricted Access to Sensitive Business Flows | Drive sensitive flows (checkout, signup, password reset) at machine speed and out of order; verify anti-automation controls and state checks hold. |
| API7:2023 | Server Side Request Forgery (SSRF) | Submit URLs pointing at internal addresses and metadata services in any URL-accepting parameter; verify the server refuses to fetch them. |
| API8:2023 | Security Misconfiguration | Check for verbose error bodies, stack traces, permissive CORS, missing security headers, and enabled debug endpoints across the inventory. |
| API9:2023 | Improper Inventory Management | Diff the discovered endpoint inventory against the documented spec; probe undocumented and versioned-but-forgotten endpoints (/v1 left behind by /v2). |
| API10:2023 | Unsafe Consumption of APIs | Where your API ingests third-party data, feed it malformed and malicious upstream responses; verify validation happens at the consumption boundary too. |
For the full list with fixes, read the OWASP API Top 10 guide, or the focused breakdown of broken function level authorization.
Pass means the attack was blocked
Security tests have the opposite shape from functional tests. A functional test passes when the request succeeds; a security test passes when the request is refused: the foreign invoice returns 404, the tampered token gets a 401, the injection string comes back inert. Qodex encodes this inversion in the scenarios themselves: pass means blocked, fail means vulnerable.
This matters because AI test tools are built to make failing tests pass, and the cheapest fix for a failing security check is always to relax the assertion and accept the leaked field. Qodex's security skill is explicitly built to never weaken a failing security assertion: a failing security test stays red until the API stops being vulnerable. High and critical findings also require captured evidence before the agent can file them, and repeat observations are deduplicated against open findings instead of flooding the queue.
Multi-role auth profiles that cross the streams
You cannot find an IDOR with one set of credentials. The bug is, by definition, about what user B can do with user A's data, so the test has to authenticate as both and cross the streams. This is why unauthenticated scanners structurally miss the number one API risk.
Qodex environments support multiple auth profiles, for example an admin, a regular user, and a viewer, each with its own credentials. The agent uses them in combination: fetch a resource as admin, replay the request as the viewer, assert the boundary holds. Auth setup is handled per environment (HTTP login flows with token extraction, or a real browser login when your auth lives behind a web form), and because these are normal scenarios, every IDOR check you author joins the same scheduled suite as your functional API tests.
# fetch as admin GET /api/v1/invoices/8412 Authorization: Bearer {{admin_token}} → 200 OK # replay as another role GET /api/v1/invoices/8412 Authorization: Bearer {{viewer_token}} # pass = the boundary holds → expected 403 / 404
Run on a schedule, on a webhook, or on demand
Active security scenarios run three ways. Because replay is deterministic, running the full OWASP suite on every deploy is an engineering decision, not a budgeting one.
On a schedule
Cron-based recurring runs: a nightly regression alongside a weekly security audit. Each schedule carries its own notification policy, so results reach the right email or Slack channel on the conditions you choose.
On a webhook
Your CI pipeline or deploy hook triggers a security run with one HTTP call, authenticated by a per-project API key. Ship to staging, fire the webhook, and get a verdict before the change reaches production.
On demand
Ask the agent in chat to audit a single endpoint for IDOR, run a tagged subset, or sweep the full OWASP suite, and watch the findings stream in live.
Plans and usage caps are on the pricing page.
See pricingManual vs automated vs continuous penetration testing
The three approaches differ in cadence and in what happens between snapshots. Continuous penetration testing keeps deterministic, scriptable attack scenarios running on every release, and is the only model where a fixed vulnerability stays tested forever.
| Manual pentest | Automated scan | Continuous (Qodex) | |
|---|---|---|---|
| Cadence | Once or twice a year, per engagement | When someone remembers to run the scanner | Every release, nightly, or on the schedule you set |
| Who finds the bugs | A human expert, for a fixed window | A scanner running canned checks | The agent authors attack scenarios; a human reviews findings |
| BOLA / IDOR coverage | Yes, if the tester logs in as two users | Usually missed; most scanners never authenticate twice | Built in: multiple auth profiles, role-crossing by default |
| Exposure window | Up to a year between a regression and its discovery | Until the next ad-hoc run | One release cycle |
| Cost per rerun | A new engagement and re-test fee | A scanner license seat | Scenarios authored once; replays add no LLM cost |
| Regression detection | Only if the next engagement re-tests it | Only if the same scan is re-run unchanged | Automatic: every fixed vulnerability stays tested |
This is not an argument against pentests. Keep them, and stop paying them to rediscover bugs a scheduled scenario would have caught in the same week they were introduced. For a tool-by-tool breakdown of the scanning options, see our comparison of API security testing tools.
Go deeper on API security
Guides on API security: the OWASP API Top 10, how to pick security tools, how to fuzz, and how penetration testing fits alongside continuous coverage.
API security testing FAQ
Comparing tools? See the best API security testing tools roundup.
API security testing sends hostile requests at your API on purpose (foreign object IDs, tampered tokens, oversized payloads, injection strings) and checks that every one of them is rejected. It is a form of dynamic application security testing (DAST): it exercises the running API rather than scanning source code. It targets the bugs scanners miss because they require authentication and context, above all broken authorization (BOLA and IDOR). In Qodex, you describe the target in plain English, the agent writes the attack scenarios, runs them, and triages every finding.
Your attackers test continuously. So should you.
Point the agent at your API, set up your auth roles, and get OWASP-aligned attack scenarios that replay on every release at zero LLM cost.