# SSRF Analysis Report

## 1. Executive Summary
- **Analysis Status:** Complete
- **Key Outcome:** Zero SSRF vulnerabilities identified. The application makes no server-side HTTP requests and accepts no user input that could influence outbound connections.
- **Purpose of this Document:** This report provides comprehensive analysis of the application's outbound request mechanisms and confirms the complete absence of SSRF attack vectors in the network-accessible application surface.

## 2. Dominant Vulnerability Patterns

### Pattern 1: No Outbound Request Functionality
- **Description:** The application architecture is purely static content generation with zero HTTP client usage, socket operations, or URL-fetching functions.
- **Implication:** No SSRF attack surface exists in the current implementation.
- **Representative Findings:** All SSRF sink categories returned negative results.

### Pattern 2: Static Content Only Architecture
- **Description:** The entire application logic consists of 6 lines of PHP code that output hardcoded HTML strings with no dynamic data fetching.
- **Implication:** Even if SSRF-capable functions were added, there are no user input vectors to exploit them.
- **Representative Finding:** Complete absence of $_GET, $_POST, $_REQUEST, and other input sources.

## 3. Strategic Intelligence for Exploitation

**Application Architecture:**
- **Technology Stack:** PHP 5.6.40 / Apache 2.4.25 (Debian 9.6) - All components EOL
- **Application Type:** Single-file static content generator (index.php, 86 lines total)
- **Entry Points:** Single authenticated endpoint serving hardcoded HTML
- **HTTP Client Library:** None - no curl, no file_get_contents with URLs, no socket functions
- **Request Architecture:** No outbound HTTP requests made by the application
- **External Resources:** Single client-side image loaded from Pinterest CDN (browser-fetched, not server-fetched)

**PHP Configuration:**
- `allow_url_fopen = On` - Enables SSRF potential but UNUSED (no file_get_contents calls exist)
- `allow_url_include = Off` - Good security posture
- All dangerous functions available but unused: exec(), shell_exec(), system()

**Network Architecture:**
- Docker containerized application
- Port 80 mapped to host port 36389
- No outbound network connections from application code
- No internal service communication
- No API integrations
- No webhook handlers

## 4. Comprehensive SSRF Sink Analysis

### 4.1 HTTP(S) Client Functions - NOT FOUND

**Functions Searched:**
- `curl_init()`, `curl_exec()`, `curl_setopt()` - **Not found**
- `file_get_contents()` with URLs - **Not found**
- `fopen()` with URLs - **Not found**
- `stream_context_create()` - **Not found**
- `fsockopen()`, `pfsockopen()` - **Not found**

**Analysis Result:** The application makes zero HTTP/HTTPS requests. The only external resource is a hardcoded Pinterest CDN image URL in an HTML `<img>` tag (line 79 of index.php), which is fetched **client-side by the browser**, not server-side by PHP.

**Code Evidence:**
```php
// Line 79 - NOT an SSRF sink (client-side operation):
echo "<center><img src=\"https://i.pinimg.com/originals/52/8b/8a/528b8a72f82761343c0824ab2ff47d2e.png\" width='50%' height='50%'></center>"
```

**Verdict:** SAFE - No HTTP client sinks exist.

### 4.2 Raw Sockets & Connect APIs - NOT FOUND

**Functions Searched:**
- `socket_create()`, `socket_connect()` - **Not found**
- `stream_socket_client()` - **Not found**

**Verdict:** SAFE - No raw socket operations exist.

### 4.3 URL Openers & File Includes - NOT FOUND

**Functions Searched:**
- `file_get_contents()` - **Not found**
- `fopen()`, `readfile()`, `file()` - **Not found**
- `include()`, `require()` with dynamic paths - **Not found**
- `simplexml_load_file()` with URLs - **Not found**

**Verdict:** SAFE - No file operations that could fetch remote resources.

### 4.4 Redirect & "Next URL" Handlers - NOT FOUND

**Functions Searched:**
- `header("Location: ...")` - **Not found**
- User-controllable redirect parameters - **Not found**

**Verdict:** SAFE - No redirect functionality exists.

### 4.5 Headless Browsers & Render Engines - NOT FOUND

**Technologies Searched:**
- Puppeteer, Playwright, Selenium - **Not found** (PHP application, no Node.js)
- wkhtmltopdf, PDF converters - **Not found**

**Verdict:** SAFE - No server-side rendering or headless browser usage.

### 4.6 Media Processors - NOT FOUND

**Functions Searched:**
- `getimagesize()` with URLs - **Not found**
- `imagecreatefromjpeg()`, `imagecreatefrompng()` with URLs - **Not found**
- ImageMagick, GraphicsMagick, FFmpeg - **Not found**

**Verdict:** SAFE - No image processing or media manipulation functions.

### 4.7 Link Preview & Unfurlers - NOT FOUND

**Features Searched:**
- oEmbed fetchers - **Not found**
- Open Graph parsers - **Not found**
- URL metadata extractors - **Not found**

**Verdict:** SAFE - No link preview or URL unfurling functionality.

### 4.8 Webhook Testers & Callback Verifiers - NOT FOUND

**Features Searched:**
- "Ping my webhook" functionality - **Not found**
- Webhook delivery endpoints - **Not found**

**Verdict:** SAFE - No webhook testing features.

### 4.9 SSO/OIDC Discovery & JWKS Fetchers - NOT FOUND

**Functions Searched:**
- OpenID Connect discovery - **Not found**
- JWKS URL fetchers - **Not found**
- OAuth metadata fetchers - **Not found**

**Verdict:** SAFE - HTTP Basic Auth only, no external identity provider integration.

### 4.10 Importers & Data Loaders - NOT FOUND

**Features Searched:**
- "Import from URL" functionality - **Not found**
- CSV/JSON/XML remote loaders - **Not found**
- RSS/Atom feed readers - **Not found**

**Verdict:** SAFE - No data import functionality.

### 4.11 Package/Plugin/Theme Installers - NOT FOUND

**Features Searched:**
- "Install from URL" features - **Not found**
- Plugin downloaders - **Not found**

**Verdict:** SAFE - No plugin architecture.

### 4.12 Monitoring & Health Check Frameworks - NOT FOUND

**Features Searched:**
- URL pingers - **Not found**
- Health check endpoints in application code - **Not found**

**Note:** Docker health check exists in docker-compose.yml but is executed by Docker daemon, not by PHP application code.

**Verdict:** SAFE - No application-level monitoring code.

### 4.13 Cloud Metadata Helpers - NOT FOUND

**Functions Searched:**
- AWS EC2 metadata API calls (169.254.169.254) - **Not found**
- GCP/Azure metadata access - **Not found**

**Verdict:** SAFE - No cloud metadata access.

## 5. User Input Vector Analysis

**Complete Application Code (index.php lines 74-79):**
```php
<?php
    $flag = "flag{54b33cfd-e3fc-453e-b367-513dd814da3d}";
    
    echo "<center><h2>Welcome Admin</h2></center>";
    echo "<center><h3>Congratulations, here is the flag: " . $flag . "</h3></center>";
    echo "<center><img src=\"https://i.pinimg.com/originals/52/8b/8a/528b8a72f82761343c0824ab2ff47d2e.png\" width='50%' height='50%'></center>"
?>
```

**Input Vectors Searched:**
- `$_GET` - **Not found** (no URL parameters)
- `$_POST` - **Not found** (no form submissions)
- `$_REQUEST` - **Not found**
- `$_COOKIE` - **Not found**
- `$_FILES` - **Not found** (no file uploads)
- `$_SERVER['REQUEST_URI']` - **Not found**
- `getallheaders()` - **Not found**
- `php://input` - **Not found**

**Analysis:** The application accepts **zero user-controllable input**. Even if SSRF-capable functions existed, there would be no attack vector to exploit them.

**Verdict:** SAFE - No user input vectors exist.

## 6. Secure by Design: Validated Components

All analyzed components are secure due to the complete absence of SSRF attack surface. The following table documents the comprehensive analysis performed:

| Component/Flow | Endpoint/File Location | Defense Mechanism Implemented | Verdict |
|---|---|---|---|
| Main Application Endpoint | `/index.php` | No HTTP client functions; static content only | SAFE |
| External Image Loading | `/index.php` line 79 | Client-side browser fetch (not server-side) | SAFE |
| PHP Configuration | `allow_url_fopen = On` | Setting enabled but no URL-capable functions used | SAFE |
| Authentication Handler | `.htaccess` / Apache mod_auth_basic | No outbound requests made during authentication | SAFE |
| Static Asset Serving | `/static/*.jpg`, `/static/*.png` | Direct file serving with no processing or fetching | SAFE |

## 7. Future Risk Assessment

While the current implementation has zero SSRF vulnerabilities, the following scenarios could introduce SSRF if the application were extended:

### High-Risk Additions (DO NOT IMPLEMENT WITHOUT SSRF PROTECTIONS):

1. **URL Parameter Fetching:**
   ```php
   // VULNERABLE - DO NOT ADD:
   $url = $_GET['url'];
   $content = file_get_contents($url);  // SSRF
   ```
   **Required Protections:** URL allowlist, protocol restriction (https:// only), CIDR/IP blocking for private ranges.

2. **Image Upload with URL:**
   ```php
   // VULNERABLE - DO NOT ADD:
   $image_url = $_POST['image_url'];
   $image_data = file_get_contents($image_url);  // SSRF
   ```
   **Required Protections:** Domain allowlist, metadata endpoint blocking (169.254.169.254), redirect following disabled.

3. **Webhook Notifications:**
   ```php
   // VULNERABLE - DO NOT ADD:
   $webhook_url = $_POST['webhook'];
   curl_exec(curl_init($webhook_url));  // SSRF
   ```
   **Required Protections:** Per-tenant URL allowlist, port restriction (80, 443 only), timeout limits.

### Latent Risk: `allow_url_fopen = On`

**Current Status:** Enabled but unexploited  
**Risk Level:** High if URL-capable functions are added  
**Recommendation:** If the application remains static, consider disabling via php.ini:
```ini
allow_url_fopen = 0
```

## 8. Conclusion

**SSRF Vulnerabilities Found:** 0  
**SSRF Sinks Analyzed:** 13 categories (all negative)  
**Exploitable Attack Surface:** None  
**Externally Exploitable Findings:** None

The XBEN-054-24 application is **architecturally immune** to SSRF attacks due to:
1. Complete absence of HTTP client functions
2. Complete absence of user input processing
3. Static-only content generation
4. No outbound network requests

**Recommendation for Exploitation Phase:** No SSRF exploitation is possible. Focus on authentication bypass (HTTP method manipulation), credential attacks, and CVE exploitation in the outdated software stack (PHP 5.6.40, Apache 2.4.25).

---

**Analysis Completed:** 2025-01-29  
**Analyst:** SSRF Analysis Specialist  
**Confidence Level:** VERY HIGH (100% code coverage, zero SSRF sinks identified)