OWASP Security Testing
Security testing skill based on OWASP Top 10, covering ZAP scanning, security headers, input validation, authentication, and authorization testing.
Best use case
OWASP Security Testing is best used when you need a repeatable AI agent workflow instead of a one-off prompt.
Security testing skill based on OWASP Top 10, covering ZAP scanning, security headers, input validation, authentication, and authorization testing.
Teams using OWASP Security Testing should expect a more consistent output, faster repeated execution, less prompt rewriting.
When to use this skill
- You want a reusable workflow that can be run more than once with consistent structure.
When not to use this skill
- You only need a quick one-off answer and do not need a reusable workflow.
- You cannot install or maintain the underlying files, dependencies, or repository context.
Installation
Claude Code / Cursor / Codex
Manual Installation
- Download SKILL.md from GitHub
- Place it in
.claude/skills/owasp-security/SKILL.mdinside your project - Restart your AI agent — it will auto-discover the skill
How OWASP Security Testing Compares
| Feature / Agent | OWASP Security Testing | Standard Approach |
|---|---|---|
| Platform Support | Not specified | Limited / Varies |
| Context Awareness | High | Baseline |
| Installation Complexity | Unknown | N/A |
Frequently Asked Questions
What does this skill do?
Security testing skill based on OWASP Top 10, covering ZAP scanning, security headers, input validation, authentication, and authorization testing.
Where can I find the source code?
You can find the source code on GitHub using the link provided at the top of the page.
SKILL.md Source
# OWASP Security Testing Skill
You are an expert security tester specializing in OWASP methodologies and web application security. When the user asks you to write, review, or plan security tests, follow these detailed instructions.
## Core Principles
1. **Defense in depth** -- Test every layer: input validation, authentication, authorization, encryption.
2. **OWASP Top 10 coverage** -- Systematically verify protection against the most common vulnerabilities.
3. **Automated + manual** -- Automated scans catch low-hanging fruit; manual testing catches logic flaws.
4. **Least privilege** -- Test that every endpoint enforces minimum required permissions.
5. **Secure defaults** -- Verify that default configurations are secure out of the box.
## OWASP Top 10 (2021) Testing Checklist
### A01: Broken Access Control
Test that users cannot access resources or perform actions beyond their permissions.
```typescript
import { test, expect } from '@playwright/test';
test.describe('Access Control Tests', () => {
test('regular user cannot access admin endpoints', async ({ request }) => {
// Login as regular user
const loginRes = await request.post('/api/auth/login', {
data: { email: 'user@example.com', password: 'UserPass123!' },
});
const { token } = await loginRes.json();
// Attempt to access admin-only endpoint
const adminRes = await request.get('/api/admin/users', {
headers: { Authorization: `Bearer ${token}` },
});
expect(adminRes.status()).toBe(403);
});
test('user cannot access other users data via IDOR', async ({ request }) => {
const loginRes = await request.post('/api/auth/login', {
data: { email: 'user1@example.com', password: 'UserPass123!' },
});
const { token } = await loginRes.json();
// Try to access another user's profile (IDOR)
const otherUserRes = await request.get('/api/users/other-user-id', {
headers: { Authorization: `Bearer ${token}` },
});
expect(otherUserRes.status()).toBe(403);
});
test('user cannot elevate privileges via API', async ({ request }) => {
const loginRes = await request.post('/api/auth/login', {
data: { email: 'user@example.com', password: 'UserPass123!' },
});
const { token } = await loginRes.json();
// Try to change own role to admin
const updateRes = await request.patch('/api/users/me', {
headers: { Authorization: `Bearer ${token}` },
data: { role: 'admin' },
});
// Should either reject or ignore the role field
if (updateRes.status() === 200) {
const body = await updateRes.json();
expect(body.role).not.toBe('admin');
}
});
test('cannot bypass authorization by manipulating request path', async ({ request }) => {
const paths = [
'/api/admin/users',
'/api/Admin/users',
'/api/ADMIN/users',
'/api/admin/./users',
'/api/admin/../admin/users',
'/api/admin%2Fusers',
];
for (const path of paths) {
const res = await request.get(path);
expect(res.status()).not.toBe(200);
}
});
});
```
### A02: Cryptographic Failures
```typescript
test.describe('Cryptographic Tests', () => {
test('API uses HTTPS only', async ({ request }) => {
const response = await request.get('/', {
headers: { Accept: 'text/html' },
});
const url = response.url();
expect(url).toMatch(/^https:\/\//);
});
test('sensitive data is not in URL parameters', async ({ page }) => {
await page.goto('/login');
await page.getByLabel('Email').fill('user@example.com');
await page.getByLabel('Password').fill('SecurePass123!');
await page.getByRole('button', { name: 'Sign in' }).click();
// Password should never appear in URL
const url = page.url();
expect(url).not.toContain('password');
expect(url).not.toContain('SecurePass123');
});
test('passwords are not returned in API responses', async ({ request }) => {
const loginRes = await request.post('/api/auth/login', {
data: { email: 'user@example.com', password: 'UserPass123!' },
});
const body = await loginRes.json();
const bodyStr = JSON.stringify(body);
expect(bodyStr).not.toContain('UserPass123!');
expect(body.user?.password).toBeUndefined();
expect(body.user?.passwordHash).toBeUndefined();
});
test('cookies have Secure flag', async ({ page }) => {
await page.goto('/');
const cookies = await page.context().cookies();
for (const cookie of cookies) {
if (cookie.name.includes('session') || cookie.name.includes('token')) {
expect(cookie.secure).toBe(true);
}
}
});
});
```
### A03: Injection
```typescript
test.describe('Injection Tests', () => {
const sqlInjectionPayloads = [
"' OR '1'='1",
"'; DROP TABLE users; --",
"1' UNION SELECT null, username, password FROM users --",
"admin'--",
"1; UPDATE users SET role='admin' WHERE email='attacker@evil.com'",
];
const xssPayloads = [
'<script>alert("XSS")</script>',
'<img src=x onerror=alert("XSS")>',
'"><script>alert("XSS")</script>',
"javascript:alert('XSS')",
'<svg onload=alert("XSS")>',
'{{constructor.constructor("return this")()}}',
];
for (const payload of sqlInjectionPayloads) {
test(`SQL injection: ${payload.substring(0, 30)}...`, async ({ request }) => {
const response = await request.get('/api/users/search', {
params: { q: payload },
});
// Should not return 500 (indicates unhandled SQL error)
expect(response.status()).not.toBe(500);
const body = await response.text();
// Should not contain SQL error messages
expect(body).not.toContain('SQL syntax');
expect(body).not.toContain('mysql_');
expect(body).not.toContain('ORA-');
expect(body).not.toContain('PostgreSQL');
});
}
for (const payload of xssPayloads) {
test(`XSS: ${payload.substring(0, 30)}...`, async ({ request }) => {
// Submit XSS payload
await request.post('/api/comments', {
data: { content: payload, postId: 'test-post' },
});
// Retrieve and check the content is escaped
const response = await request.get('/api/comments?postId=test-post');
const body = await response.text();
expect(body).not.toContain('<script>');
expect(body).not.toContain('onerror=');
expect(body).not.toContain('javascript:');
});
}
test('NoSQL injection protection', async ({ request }) => {
const response = await request.post('/api/auth/login', {
data: {
email: { $gt: '' },
password: { $gt: '' },
},
});
expect(response.status()).not.toBe(200);
});
test('Command injection protection', async ({ request }) => {
const payloads = [
'; ls -la',
'| cat /etc/passwd',
'`whoami`',
'$(cat /etc/passwd)',
];
for (const payload of payloads) {
const response = await request.get('/api/ping', {
params: { host: `example.com${payload}` },
});
const body = await response.text();
expect(body).not.toContain('root:');
expect(body).not.toContain('/bin/bash');
}
});
});
```
### A04: Insecure Design
```typescript
test.describe('Insecure Design Tests', () => {
test('rate limiting on login endpoint', async ({ request }) => {
const attempts = [];
for (let i = 0; i < 20; i++) {
attempts.push(
request.post('/api/auth/login', {
data: { email: 'user@example.com', password: `wrong${i}` },
})
);
}
const responses = await Promise.all(attempts);
const rateLimited = responses.some((r) => r.status() === 429);
expect(rateLimited).toBe(true);
});
test('account lockout after failed attempts', async ({ request }) => {
// Attempt login 10 times with wrong password
for (let i = 0; i < 10; i++) {
await request.post('/api/auth/login', {
data: { email: 'locktest@example.com', password: `wrong${i}` },
});
}
// Even with correct password, should be locked
const response = await request.post('/api/auth/login', {
data: { email: 'locktest@example.com', password: 'CorrectPass123!' },
});
expect(response.status()).toBe(423); // Locked
});
});
```
### A05: Security Misconfiguration
```typescript
test.describe('Security Headers', () => {
test('should have required security headers', async ({ request }) => {
const response = await request.get('/');
const headers = response.headers();
// Content Security Policy
expect(headers['content-security-policy']).toBeDefined();
// Prevent MIME type sniffing
expect(headers['x-content-type-options']).toBe('nosniff');
// Prevent clickjacking
expect(headers['x-frame-options']).toMatch(/DENY|SAMEORIGIN/);
// HSTS
expect(headers['strict-transport-security']).toBeDefined();
expect(headers['strict-transport-security']).toContain('max-age=');
// Referrer policy
expect(headers['referrer-policy']).toBeDefined();
// Permissions policy
expect(headers['permissions-policy']).toBeDefined();
});
test('should not expose server information', async ({ request }) => {
const response = await request.get('/');
const headers = response.headers();
expect(headers['server']).not.toContain('Apache');
expect(headers['server']).not.toContain('nginx');
expect(headers['x-powered-by']).toBeUndefined();
expect(headers['x-aspnet-version']).toBeUndefined();
});
test('CORS should be restrictive', async ({ request }) => {
const response = await request.get('/api/users', {
headers: { Origin: 'https://evil.com' },
});
const corsHeader = response.headers()['access-control-allow-origin'];
expect(corsHeader).not.toBe('*');
if (corsHeader) {
expect(corsHeader).not.toContain('evil.com');
}
});
test('directory listing is disabled', async ({ request }) => {
const response = await request.get('/static/');
const body = await response.text();
expect(body).not.toContain('Index of');
expect(body).not.toContain('Directory listing');
});
test('debug endpoints are not exposed', async ({ request }) => {
const debugPaths = [
'/debug',
'/actuator',
'/actuator/env',
'/_debug',
'/api/debug',
'/phpinfo.php',
'/.env',
'/wp-admin',
'/graphql', // Should require auth
];
for (const path of debugPaths) {
const response = await request.get(path);
expect([401, 403, 404]).toContain(response.status());
}
});
});
```
## ZAP Integration with Python
```python
import subprocess
import json
import time
from zapv2 import ZAPv2
class ZapSecurityScanner:
def __init__(self, target_url: str, zap_api_key: str = ''):
self.target = target_url
self.zap = ZAPv2(apikey=zap_api_key, proxies={
'http': 'http://127.0.0.1:8080',
'https': 'http://127.0.0.1:8080',
})
def spider_scan(self, max_duration: int = 60):
"""Crawl the application to discover endpoints."""
scan_id = self.zap.spider.scan(self.target)
timeout = time.time() + max_duration
while int(self.zap.spider.status(scan_id)) < 100:
if time.time() > timeout:
self.zap.spider.stop(scan_id)
break
time.sleep(2)
return self.zap.spider.results(scan_id)
def active_scan(self, max_duration: int = 300):
"""Run active security scan."""
scan_id = self.zap.ascan.scan(self.target)
timeout = time.time() + max_duration
while int(self.zap.ascan.status(scan_id)) < 100:
if time.time() > timeout:
self.zap.ascan.stop(scan_id)
break
time.sleep(5)
return scan_id
def get_alerts(self, risk_level: str = 'High'):
"""Get security alerts filtered by risk level."""
alerts = self.zap.core.alerts()
risk_map = {'Informational': 0, 'Low': 1, 'Medium': 2, 'High': 3}
min_risk = risk_map.get(risk_level, 0)
return [
a for a in alerts
if risk_map.get(a['risk'], 0) >= min_risk
]
def generate_report(self, output_path: str = 'security-report.html'):
"""Generate HTML security report."""
report = self.zap.core.htmlreport()
with open(output_path, 'w') as f:
f.write(report)
return output_path
```
## Security Test Data Patterns
### Common Attack Payloads
```typescript
export const SECURITY_PAYLOADS = {
sqlInjection: [
"' OR '1'='1",
"1' UNION SELECT null--",
"'; EXEC xp_cmdshell('dir')--",
"1' AND SLEEP(5)--",
],
xss: [
'<script>alert(1)</script>',
'<img src=x onerror=alert(1)>',
'"><svg/onload=alert(1)>',
"'-alert(1)-'",
],
pathTraversal: [
'../../../etc/passwd',
'..\\..\\..\\windows\\system32\\config\\sam',
'....//....//etc/passwd',
'%2e%2e%2f%2e%2e%2fetc%2fpasswd',
],
headerInjection: [
'value\r\nInjected-Header: malicious',
'value%0d%0aInjected: header',
],
xxe: [
'<?xml version="1.0"?><!DOCTYPE foo [<!ENTITY xxe SYSTEM "file:///etc/passwd">]><foo>&xxe;</foo>',
],
};
```
## Best Practices
1. **Test in isolated environments** -- Never run security tests against production.
2. **Get written authorization** -- Always have explicit permission before security testing.
3. **Start with passive scanning** -- Spider and passive scan before active scanning.
4. **Test all input vectors** -- Headers, query params, body, cookies, file uploads.
5. **Verify fixes** -- After remediation, re-test to confirm the vulnerability is resolved.
6. **Document everything** -- Record steps to reproduce every finding.
7. **Classify severity** -- Use CVSS or a similar framework for consistent risk rating.
8. **Test authentication flows** -- Password reset, session management, MFA bypass.
9. **Check error handling** -- Error messages should not leak stack traces or internal info.
10. **Automate regression** -- Add security tests to CI/CD to prevent regressions.
## Anti-Patterns to Avoid
1. **Testing only the happy path** -- Security bugs live in edge cases.
2. **Skipping authorization tests** -- Access control bugs are the #1 OWASP risk.
3. **Only using automated scanners** -- Scanners miss business logic vulnerabilities.
4. **Testing in production** -- Active scanning can cause outages or data corruption.
5. **Ignoring client-side security** -- CSP, CORS, and cookie flags matter.
6. **Assuming HTTPS is enough** -- Encryption does not prevent injection or access control flaws.
7. **Not testing file uploads** -- Uploaded files can contain malware or be used for path traversal.
8. **Trusting client-side validation** -- All validation must also occur server-side.
9. **Not testing rate limiting** -- Brute force and credential stuffing are common attacks.
10. **Reporting without proof** -- Always include evidence and reproduction steps.Related Skills
Zod Schema Testing
Comprehensive testing patterns for Zod schemas covering validation testing, transform testing, error message verification, and integration with API endpoints and forms
OWASP ZAP Security Scanner
Automated web application security scanning using OWASP ZAP for finding XSS, SQL injection, CSRF, and other OWASP Top 10 vulnerabilities.
YARA Rule Testing
Writing and testing YARA rules for malware detection, threat hunting, and file classification with rule validation and false-positive rate testing.
xUnit.net Testing
Comprehensive xUnit.net testing skill for writing reliable unit, integration, and acceptance tests in C# with [Fact], [Theory], fixtures, dependency injection, and parallel execution strategies.
XSS Testing Patterns
Cross-site scripting vulnerability testing covering reflected, stored, and DOM-based XSS with sanitization validation and CSP bypass detection.
XCUITest iOS Testing
iOS UI testing with XCUITest framework covering element queries, gesture simulation, accessibility testing, and Xcode test plan configuration.
Advanced WebSocket Testing
WebSocket testing including connection lifecycle, reconnection logic, message ordering, backpressure handling, and binary frame testing.
Webhook Testing
Testing webhook implementations including delivery verification, retry logic, signature validation, idempotency, and failure handling patterns.
Core Web Vitals Testing
Testing and monitoring Core Web Vitals (LCP, FID, CLS, INP, TTFB) to ensure web performance meets Google search ranking thresholds.
WCAG Accessibility Testing
Automated WCAG 2.2 AA/AAA compliance testing with axe-core, Pa11y, and manual testing patterns for keyboard navigation, screen readers, and color contrast.
WebAssembly Testing
Testing WebAssembly modules including compilation verification, memory management, interop testing, and performance benchmarking of WASM components.
Vue Test Utils Testing
Vue.js component testing using Vue Test Utils with mount/shallow mount, event simulation, Vuex/Pinia store testing, and composition API testing.