# SSRF Analysis Report

## 1. Executive Summary
- **Analysis Status:** Complete
- **Key Outcome:** No Server-Side Request Forgery (SSRF) vulnerabilities were identified in the XBEN-021-24 application. The application does not make any user-influenced outbound HTTP requests and has zero SSRF attack surface.
- **Purpose of this Document:** This report provides comprehensive documentation that the application's architecture does not include SSRF-vulnerable functionality, confirming that no outbound HTTP requests are made based on user input.

## 2. Dominant Vulnerability Patterns

**NO SSRF PATTERNS IDENTIFIED**

After systematic analysis of all network-accessible endpoints and application code, the following patterns were specifically evaluated and found to be **absent**:

### Pattern 1: URL Parameter Processing (NOT PRESENT)
- **Description:** Endpoints that accept URL parameters and use them to make server-side HTTP requests.
- **Search Results:** No endpoints accept URL, webhook_url, callback_url, or similar parameters.
- **Implication:** This common SSRF attack vector is not present.

### Pattern 2: Redirect Following (NOT PRESENT)
- **Description:** Server-side redirect following based on user input.
- **Analysis:** The single `RedirectResponse` in the application (main.py:95) uses database-derived integer IDs, not user-controlled URLs.
- **Implication:** No redirect-based SSRF vulnerabilities exist.

### Pattern 3: External Resource Fetching (NOT PRESENT)
- **Description:** Image processing, PDF generation, or media fetching from URLs.
- **Search Results:** No file upload functionality, no image processing, no URL-based resource fetching.
- **Implication:** No SSRF through media processing pipelines.

### Pattern 4: Webhook/Callback Mechanisms (NOT PRESENT)
- **Description:** Endpoints that accept callback URLs and perform server-side requests.
- **Search Results:** No webhook functionality, no callback endpoints.
- **Implication:** No webhook-based SSRF vectors.

### Pattern 5: API Proxy Functionality (NOT PRESENT)
- **Description:** Endpoints that proxy requests to other services based on user input.
- **Search Results:** The application is self-contained with only SQLite database access.
- **Implication:** No proxy-based SSRF vulnerabilities.

### Pattern 6: External Service Integration (NOT PRESENT)
- **Description:** OAuth2 callbacks, JWKS fetching, or other external service integrations.
- **Search Results:** Despite OAuth2-related imports, no actual external OAuth2 implementation exists. No JWKS fetching functionality.
- **Implication:** No integration-based SSRF vectors.

## 3. Strategic Intelligence for Exploitation

**HTTP Client Analysis:**
- **Libraries Present:** httpx==0.27.0 and httpcore==1.0.5 are listed in requirements.txt as transitive dependencies
- **Libraries Used:** NONE - No HTTP client libraries are imported or used in application code
- **Request Architecture:** The application makes zero outbound HTTP requests. All functionality is database-driven (SQLAlchemy + SQLite)

**Application Architecture:**
- **Type:** Monolithic FastAPI application with server-side rendering (Jinja2 templates)
- **External Communication:** None - No external service dependencies
- **Internal Services:** SQLite database file access only (local filesystem, not network-based)

**Redirect Analysis:**
```python
# /app/main.py:95
response = RedirectResponse(url=f"/company/{company.id}/jobs", status_code=status.HTTP_303_SEE_OTHER)
```
- **Assessment:** SAFE
- **Reason:** company.id is an auto-incremented integer from database, not user-controlled
- **URL Format:** Internal relative path (/company/{id}/jobs)
- **SSRF Risk:** None - Cannot redirect to external URLs or internal network resources

**File Operations:**
```python
# /app/main.py:72-73
with open("flag.txt") as f:
    flag = f.read()
```
- **Assessment:** SAFE
- **Reason:** Hardcoded filename, not user-controlled
- **Purpose:** Reads CTF flag during startup
- **SSRF Risk:** None - Local file read with static path

## 4. Secure by Design: Validated Components

All network-accessible components were analyzed and confirmed to have no SSRF attack surface:

| Component/Flow | Endpoint/File Location | Defense Mechanism Implemented | Verdict |
|---|---|---|---|
| Login Authentication | POST /token (main.py:87-97) | No URL parameters accepted, no outbound requests made | SAFE |
| Job Listings Display | GET /company/{id}/jobs (main.py:105-115) | Database-only queries, no external resource fetching | SAFE |
| Profile Update | POST /edit_profile/{id} (main.py:152-162) | Accepts name and is_admin form fields only, no URL processing | SAFE |
| Application Redirect | RedirectResponse (main.py:95) | Uses database-derived integer ID, internal path construction | SAFE |
| Startup Flag Reading | File read (main.py:72-73) | Hardcoded filename "flag.txt", not user-influenced | SAFE |
| Template Rendering | Jinja2 templates (all) | No JavaScript, no fetch() calls, no client-side HTTP requests | SAFE |

## 5. Comprehensive Analysis Scope

### Endpoints Analyzed

All 6 network-accessible HTTP endpoints were systematically analyzed:

1. **GET /** - Login page
   - Parameters: None
   - SSRF Risk: None
   
2. **POST /token** - Authentication
   - Parameters: username, password (form fields)
   - SSRF Risk: None - No URL processing
   
3. **GET /ping** - Health check
   - Parameters: None
   - SSRF Risk: None
   
4. **GET /company/{company_id}/jobs** - Job listings
   - Parameters: company_id (integer path parameter)
   - SSRF Risk: None - Only database queries
   
5. **GET /edit_profile/{company_id}** - Profile form
   - Parameters: company_id (integer path parameter)
   - SSRF Risk: None - Renders form only
   
6. **POST /edit_profile/{company_id}** - Profile update
   - Parameters: company_id (path), name (form), is_admin (form)
   - SSRF Risk: None - No URL parameters

### Code Files Analyzed

- `/app/main.py` (163 lines) - All route handlers and authentication logic
- `/app/crud.py` (45 lines) - Database operations
- `/app/database.py` (11 lines) - Database configuration
- `/app/models.py` (24 lines) - SQLAlchemy models
- `/app/schemas.py` (47 lines) - Pydantic schemas
- `/app/templates/*.html` (4 template files) - Frontend rendering

### Import Statement Verification

**All imports reviewed - No HTTP client libraries found:**
- ❌ No `import httpx`
- ❌ No `import requests`
- ❌ No `import urllib`
- ❌ No `import aiohttp`
- ❌ No `import http.client`
- ❌ No socket operations

**Only framework and database imports present:**
- ✅ FastAPI framework components
- ✅ SQLAlchemy database ORM
- ✅ Pydantic validation
- ✅ Jinja2 templating
- ✅ Passlib/bcrypt (password hashing)
- ✅ python-jose (imported but unused)

### SSRF Sink Patterns Searched

The following SSRF sink patterns were specifically searched for and **confirmed absent**:

#### HTTP Request Sinks
- `httpx.get()`, `httpx.post()`, `httpx.request()`
- `requests.get()`, `requests.post()`, `requests.request()`
- `urllib.request.urlopen()`
- `aiohttp.ClientSession().get()`
- `http.client.HTTPConnection().request()`

#### URL Processing Sinks
- URL parameters in endpoints (e.g., ?url=, &callback=, &webhook_url=)
- Form fields accepting URLs
- JSON body fields with URL values
- HTTP header-based URL injection

#### Redirect Sinks
- User-controlled redirect destinations
- Open redirect vulnerabilities
- Meta refresh tags with user input
- JavaScript-based redirects with user data

#### File Inclusion Sinks
- `open()` with user-controlled paths
- File inclusion via URL schemes (file://, ftp://)
- XML external entity (XXE) vulnerabilities
- SVG file processing with embedded URLs

#### Media Processing Sinks
- Image fetching from URLs
- PDF generation from URLs
- HTML-to-PDF converters with URL input
- Video/audio streaming from URLs

#### Integration Sinks
- Webhook callback URL processing
- OAuth2 authorization callbacks
- SAML/OIDC redirect_uri handling
- JWKS endpoint fetching

**Result: ZERO matches for any SSRF sink pattern**

## 6. Methodology Applied

### Backward Taint Analysis (Not Applicable)

Normally, SSRF analysis would trace data flow from user input to HTTP client sinks using backward taint analysis. However, since **no HTTP client sinks exist** in this application, backward taint analysis is not applicable.

### Defense Validation (Not Applicable)

The following defense mechanisms were evaluated but found to be **not applicable** due to absence of HTTP client functionality:

- ❌ URL scheme allowlisting (http://, https://) - N/A
- ❌ Hostname/domain allowlisting - N/A
- ❌ IP address blocklisting (RFC 1918, 127.0.0.0/8, 169.254.169.254) - N/A
- ❌ Port restrictions - N/A
- ❌ DNS rebinding protection - N/A
- ❌ Request timeout configuration - N/A
- ❌ Redirect following restrictions - N/A

**Conclusion:** Since the application makes no outbound HTTP requests, these defenses are not required.

## 7. Testing Methodology Summary

### Static Code Analysis
- ✅ Analyzed all Python source files for HTTP client usage
- ✅ Reviewed all endpoint definitions for URL parameters
- ✅ Inspected all form definitions for URL input fields
- ✅ Examined all redirect logic for user-controlled destinations
- ✅ Verified all file operations use hardcoded paths

### Dynamic Analysis (Minimal)
- The reconnaissance deliverable already confirmed no SSRF-related parameters through endpoint testing
- No dynamic testing required given clear absence of SSRF functionality in code

### Import Dependency Analysis
- ✅ Reviewed requirements.txt for HTTP client libraries
- ✅ Confirmed httpx/httpcore are transitive dependencies, not directly used
- ✅ Verified no imports of HTTP client libraries in application code

## 8. Conclusion

**SSRF VULNERABILITY COUNT: 0**

The XBEN-021-24 application has **ZERO SSRF attack surface**. The application architecture is fundamentally incompatible with SSRF vulnerabilities because:

1. **No Outbound HTTP Requests:** The application makes no server-side HTTP requests to external services
2. **No URL Processing:** No endpoints accept or process URL parameters
3. **No External Integrations:** The application is self-contained with only local database access
4. **No Media Fetching:** No image processing, PDF generation, or URL-based resource fetching
5. **No Webhooks:** No callback or webhook functionality
6. **Safe Redirects:** The single redirect uses database IDs and internal paths only

**External Exploitability:** N/A - No SSRF vulnerabilities to exploit

**Recommendation:** No remediation required. The application's architecture inherently prevents SSRF attacks. However, note that this finding does not address the critical authentication bypass (Base64 token forgery) and privilege escalation vulnerabilities documented in the reconnaissance report.
