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Cyber Guards

Your APIs are your business. We test them like attackers would.

APIs power modern applications — but they also expose sensitive data, authentication workflows, and business logic directly to the internet. At CyberGuards.ai, our API penetration testing services simulate real-world attacks on your endpoints to uncover vulnerabilities before malicious actors exploit them.

Unlike automated API scanners, we don’t just flag potential risks. We exploit them, chain them, and show you the business impact.

Why API Security Testing Matters

APIs are the fastest-growing attack vector in today’s threat landscape:
90% of web-enabled apps now rely on APIs for critical functions.
OWASP ranks API security flaws — like broken authentication and IDOR — as some of the most damaging vulnerabilities.
Compliance standards such as SOC 2, PCI DSS, HIPAA, and GDPR explicitly require API security testing to protect sensitive data.

A simple API penetration test isn’t about finding bugs — it’s about proving whether attackers can bypass authentication, manipulate data, or chain exploits into a full breach.

What We Test

Our API penetration testing services target REST, GraphQL, and SOAP endpoints, focusing on:

Authentication & Authorization

broken flows, weak tokens, privilege escalation

IDOR (Insecure Direct Object References)

unauthorized access to objects and records

Excessive Data Exposure

 unnecessary fields leaking sensitive data

Injection Flaws

SQLi, NoSQL injection, command injection

Business Logic Flaws

abusing intended API workflows to bypass controls

Chained Exploits

combining small issues into impactful attack paths

Every finding is manually validated with proof-of-concept exploits. No noise, no false positives.

How It Works

Discovery

We fingerprint your APIs — endpoints, parameters, authentication flows, and integrations.

Exploitation

We simulate malicious API calls, tamper with inputs, bypass auth, and chain vulnerabilities together.

Reporting

You receive a detailed report with validated findings, severity ratings, reproduction steps, and developer-friendly remediation guidance.

Re-Testing

Once you fix the issues, we re-test — free of charge — to ensure they’re closed.

Why API Pentesting Is Different

Unlike web apps, APIs expose raw functionality directly to attackers. A single misconfigured endpoint can lead to massive data exposure. Automated scanners cannot reason about workflow flaws or chained exploits.

Our API penetration testing services focus on human-led adversarial testing — because APIs demand it.

What You Get

Manual, tool-assisted API penetration testing — no black-box automation
Exploitable findings with screenshots, payloads, and logs
Business context for every issue, not just CVSS scores
Executive summary for leadership and auditors
Free retest to confirm vulnerabilities are fixed

Common Use Cases

  • Launching new APIs or integrations
  • Quarterly or annual API security validation
  • Compliance-driven testing (SOC 2, PCI DSS, HIPAA, ISO 27001, GDPR)
  • Post-migration testing for cloud-native or microservices environments
  • Vendor due diligence and security audits

Why Choose CyberGuards.ai?

100% manual API penetration testing — no reliance on scanners
Exploitable proof with real-world attack chains
Compliance-ready reports trusted by auditors and regulators
Free re-testing included
Local expertise: API penetration testing in San Francisco, Los Angeles, and across California

FAQs

How is API security testing different from traditional web application testing?

Traditional testing focuses on HTML-based user interfaces. API security testing targets the application logic and data endpoints directly, specializing in finding flaws like broken object level authorization (BOLA), excessive data exposure, and mass assignment that are invisible to standard web scanners.
What types of APIs do you test?

We are experts in testing all major API architectures, including REST APIs, GraphQL, SOAP/WSDL, and gRPC. Each type requires a different testing methodology, and our team is proficient in the unique security challenges of each.

Our API schema is not fully documented. Can you still test it effectively?

Yes. We use a combination of traffic analysis, reverse engineering, and fuzzing techniques to discover and map your API endpoints, including hidden or undocumented ones. This "gray-box" approach is often more effective at finding real-world vulnerabilities.

What deliverables do you provide after the API security test?

You receive a comprehensive report including an executive summary, a detailed technical breakdown of each vulnerability with proof-of-concept exploits, a risk assessment based on potential business impact, and clear, actionable remediation steps tailored for your development team.

Do we need to replace our current API security platform with your service?

Not at all. Our manual API security testing service complements your existing API security platform. While platforms provide continuous monitoring and governance, our expert-led penetration testing performs deep, adversarial simulations to find complex vulnerabilities and logic flaws that automated platforms often miss.

How do you handle authentication and authorization during API testing, especially with complex tokens like JWTs?

We thoroughly test the entire authentication and authorization flow. This includes analyzing the strength of JWT implementation, testing for token leakage, validating session management, and exploiting weaknesses in access control checks to escalate privileges horizontally and vertically.

How do you test for business logic flaws specific to our API's function?

We analyze your API's intended behavior and then craft malicious requests to subvert it. This involves testing sequence bypasses, manipulating price calculations, exploiting workflow vulnerabilities, and chaining smaller issues to achieve a significant business impact.

Ready to See Your APIs Through an Attacker’s Eyes?

Your APIs are your product — and your biggest risk. Don’t let attackers find the flaws first.

 CyberGuards.ai delivers API penetration testing services in California and nationwide that validate your endpoints before attackers exploit them.

Request a Free Scope Review
Request a Free Scope Review today and receive a fixed-price proposal within 24 hours.