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Application Security Standards

Free 17-page guide

The OWASP API Security Top 10, built for teams that ship APIs.

All ten risks in one practical guide: what each one is, a real attack example, and the exact controls that stop it. Plus a checklist to audit your own APIs this week.

  • Recognize the authorization flaws that pass code review but quietly leak customer data.
  • Give your team one shared reference instead of ten scattered blog posts.
  • Walk into your next audit with a checklist mapped to every risk.

See it in action

One changed digit. Someone else's data.

api1_bola.http
GET /api/accounts/12345 200 OK your account GET /api/accounts/12346 200 OK someone else's <- BOLA

Broken Object Level Authorization is the number one risk on the list, and one of the easiest to miss in review. The guide shows how it happens, why it slips through, and the checks that close it - for all ten risks.

What's inside

Ten risks. One reference your team can act on.

Each section covers what the risk is, a real example, why it happens, the potential impact, and the controls that prevent it - plus a checklist to audit your own APIs.

API1
Broken Object Level Authorization
Users reaching records that belong to someone else by changing an ID.
API2
Broken Authentication
Weak tokens, missing MFA, and sessions that let attackers impersonate users.
API3
Broken Object Property Level Authorization
Exposing or letting users edit fields they were never meant to touch.
API4
Unrestricted Resource Consumption
No limits on requests, uploads, or queries - leading to outages and cloud bills.
API5
Broken Function Level Authorization
Standard users reaching admin-only endpoints and actions.
API6
Unrestricted Access to Sensitive Business Flows
Bots abusing legitimate workflows at scale - scalping, fraud, hoarding.
API7
Server-Side Request Forgery
Tricking your server into calling internal systems and cloud metadata.
API8
Security Misconfiguration
Default credentials, debug modes, and permissive settings shipped to production.
API9
Improper Inventory Management
Shadow and deprecated APIs that nobody is tracking or patching.
API10
Unsafe Consumption of APIs
Trusting third-party APIs without validating what comes back.

Why it matters

#1

Broken Object Level Authorization has held the top spot on the OWASP API Security list since 2019.

Source: OWASP API Security Top 10

  • Built on the current standard. Maps directly to the OWASP API Security Top 10, 2023 edition.
  • Written for practitioners. Real endpoints and attack examples, not abstract theory.
  • Action over awareness. Every risk ends with the specific controls that prevent it.
  • Vendor-neutral. No tool to buy. Use it with whatever stack you already run.
Example - replace before launch
"A quote here from a real reader - an engineer, security lead, or CISO who used the guide - is the single highest-impact thing to add."

Name, Title, Company

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The OWASP API Security Top 10, explained and ready to act on.

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