Web App Pentest

---
name: web-app-pentest
description: "Use when testing a web application for security vulnerabilities — authentication/session, access control (IDOR/privilege escalation), injection (SQLi, XSS, SSTI, command), SSRF, file upload, business logic, CSRF, and misconfiguration. Follows the OWASP Web Security Testing Guide (WSTG) and maps to the OWASP Top 10 (2021), with test steps, detection, and remediation. Authorized engagements only."
---

# Web Application Penetration Testing

Structured web app assessment following the **OWASP WSTG**, with findings mapped to the **OWASP Top 10 (2021)**. Each technique pairs the offensive test with a detection signal and a fix.

## 0. Authorization gate
- [ ] Written scope: URLs, environments, test accounts (per role).
- [ ] Destructive-action rules; data-handling rules for any PII found.
- [ ] Testing window + WAF/rate-limit expectations + emergency contact.

## 1. Methodology (WSTG phases)
```
Recon/mapping ─► Config & deploy ─► Identity/auth/session ─► Authorization
      └─► Input validation (injection) ─► Business logic ─► Client-side ─► Report
```
Enumerate every route, parameter, role, and state transition before deep testing.

## 2. Test areas (OWASP Top 10 2021 mapping)

### Broken Access Control (A01)
- **IDOR/BOLA:** change object identifiers across accounts/roles.
- **Vertical/horizontal privilege escalation:** access admin functions as a user; access peer data.
- **Forced browsing / method tampering / missing function-level checks.**
- **Fix:** deny-by-default, server-side object + function authorization on every request.

### Cryptographic Failures (A02)
- Weak TLS, sensitive data in cleartext, weak password hashing, secrets in responses.
- **Fix:** TLS 1.2+/HSTS, strong hashing (Argon2id/bcrypt), no secrets client-side.

### Injection (A03)
- **SQL/NoSQL injection**, **command injection**, **XSS** (reflected/stored/DOM), **SSTI**, header/LDAP injection.
- **Detect:** error/behavior differentials, out-of-band callbacks (in scope), template evaluation.
- **Fix:** parameterized queries, context-aware output encoding, template sandboxing, input allow-lists.

### Insecure Design (A04)
- Missing rate limits, weak workflows, trust assumptions. Pair with `threat-model`.

### Security Misconfiguration (A05)
- Default creds, verbose errors, directory listing, missing headers, permissive CORS, exposed admin/debug.
- **Fix:** hardened baseline, generic errors, least-privilege CORS, security headers.

### Vulnerable & Outdated Components (A06)
- Fingerprint versions; map to known CVEs (validate, don't just report scanner output).

### Identification & Authentication Failures (A07)
- Credential stuffing resistance, weak lockout, session fixation, predictable tokens, JWT flaws, weak password reset, MFA gaps.
- **Fix:** strong session management, MFA on sensitive ops, secure reset flows.

### Software & Data Integrity Failures (A08)
- Insecure deserialization, unsigned updates, CI/CD trust issues.

### Security Logging & Monitoring Failures (A09)
- Are security-relevant events logged and alertable? (Verify with the defender.)

### SSRF (A10)
- URL-fetching features → internal targets, cloud metadata, redirect chains (in scope).
- **Fix:** destination allow-lists, block internal/link-local ranges, validate redirects.

## 3. Business logic
Race conditions, workflow bypass, price/quantity manipulation, replay, coupon/limit abuse — often the highest-impact, scanner-invisible bugs. Model the intended flow, then break the assumptions.

## 4. Tooling
Burp Suite / ZAP (proxy + active scan), ffuf/feroxbuster (content), sqlmap (validate manually), nuclei (known CVEs), browser devtools for DOM/SPA. Note SPA/API-heavy apps → also use `api-security-audit`.

## 5. Reporting
Per finding: title, OWASP category, URL/param, severity (CVSS + business impact), reproduction, evidence (redacted), remediation. See the report template in `api-security-audit/references/report-template.md` (same structure). Checklist: `references/web-checklist.md`.

---
<sub>© 2026 noahfranklin · Part of the [Gideon](https://github.com/noahfranklin/gideon) security suite · MIT License · Original work.</sub>