# SSRF Analysis Report

## 1. Executive Summary

- **Analysis Status:** Complete
- **Key Outcome:** Zero Server-Side Request Forgery (SSRF) vulnerabilities identified. The application performs no outbound HTTP requests and has no SSRF attack surface.
- **Purpose of this Document:** This report provides comprehensive documentation that the FastAPI job listing platform is completely isolated from external network resources, with no functionality that could be exploited for SSRF attacks. The application's architecture eliminates entire classes of SSRF vulnerabilities.

**Summary of Findings:**
- **Total SSRF Sinks Found:** 0
- **Externally Exploitable SSRF Vulnerabilities:** 0
- **HTTP Client Usage:** None (httpx listed in requirements.txt but never used)
- **URL Parameters:** None
- **Outbound Requests:** None
- **Webhook/Callback Functionality:** None
- **External API Integrations:** None

**Application Architecture:**
The target application is a self-contained FastAPI-based job listing platform that interacts exclusively with a local SQLite database. All operations are internal:
- HTTP requests from users → FastAPI endpoints
- Database operations → Local SQLite file (test.db)
- Template rendering → Jinja2 (server-side)
- Authentication → Local JWT validation (python-jose)

**No external network calls are made by the application.**

## 2. Dominant Vulnerability Patterns

### Pattern Analysis: No SSRF Patterns Detected

After systematic analysis of all application endpoints, HTTP client usage, URL parameter handling, redirect logic, and external integrations, **no SSRF vulnerability patterns were identified**.

The application exhibits the following security-positive architectural characteristics:

**1. Zero Outbound HTTP Request Functionality**
- **Description:** The application does not make any HTTP/HTTPS requests to external services, APIs, or resources.
- **Security Impact:** Eliminates the primary attack vector for SSRF vulnerabilities.
- **Evidence:** 
  - No HTTP client library imports (httpx, requests, urllib, aiohttp)
  - No URL fetching functionality
  - No webhook callbacks
  - No external API integrations

**2. No URL Parameter Acceptance**
- **Description:** No endpoints accept URL, callback_url, webhook_url, redirect_to, or similar user-controllable URL parameters.
- **Security Impact:** Prevents attackers from injecting malicious URLs into server-side request operations.
- **Evidence:**
  - All form parameters are: `username` (str), `password` (str), `name` (str), `level` (bool)
  - Path parameters are: `company_id` (int)
  - No URL-like parameters exist in the codebase

**3. Safe Redirect Implementation**
- **Description:** The single redirect in the application (line 103 of main.py) uses database-derived integer IDs, not user-controllable URLs.
- **Security Impact:** Prevents open redirect and SSRF via redirect manipulation.
- **Evidence:**
  - Redirect URL: `f"/company/{company.id}/jobs"`
  - `company.id` is an integer primary key from database, not user input
  - URL is always relative (starts with `/`), never absolute

## 3. Strategic Intelligence for Exploitation

**N/A - No SSRF vulnerabilities exist for exploitation.**

### Application Architecture Analysis

**HTTP Client Library Status:**
- **httpx v0.27.0**: Listed in `/app/requirements.txt` line 17, but **NEVER imported or used** in application code
- **Recommendation**: Remove unused dependency to reduce supply chain risk

**Request Architecture:**
The application follows a simple request-response pattern with no external network interactions:
```
User Browser → FastAPI Endpoint → SQLite Database → FastAPI → HTML Template → User Browser
```

**Internal Services:**
- **SQLite Database**: `/app/test.db` (local file, no network exposure)
- **Uvicorn ASGI Server**: Handles HTTP on port 80
- **No other services**: No message queues, cache servers, or external APIs

**Network Boundaries:**
- **Inbound**: HTTP requests on port 80 (41169 mapped)
- **Outbound**: NONE
- **Internal**: File system access only (SQLite database, templates, flag.txt)

### Endpoint Analysis Results

All 9 endpoints were systematically analyzed for SSRF potential:

| Endpoint | Method | SSRF Risk Assessment |
|----------|--------|---------------------|
| `/` | GET | No URL parameters, renders login template only |
| `/token` | POST | Accepts username/password, no outbound requests |
| `/company/{company_id}/jobs` | GET | Path parameter is integer, queries local database only |
| `/edit_profile/{company_id}` | GET | Path parameter is integer, queries local database only |
| `/edit_profile/{company_id}` | POST | Accepts name (str) and level (bool), no URL parameters |
| `/ping` | GET | Returns static JSON, no user input |
| `/docs` | GET | FastAPI auto-generated, no SSRF risk |
| `/redoc` | GET | FastAPI auto-generated, no SSRF risk |
| `/openapi.json` | GET | FastAPI auto-generated, no SSRF risk |

**Verdict:** Zero endpoints exhibit SSRF vulnerability characteristics.

### File Operations Analysis

**Single file operation identified:**
- **Location**: `/app/main.py:78-79`
- **Code**: `with open("flag.txt") as f: flag = f.read()`
- **Context**: Startup event handler (`@app.on_event("startup")`)
- **Filename**: Hardcoded string literal "flag.txt"
- **User Control**: None
- **Network Access**: None (local file system only)
- **SSRF Risk**: None

**Verdict:** File operation is safe - no user-controllable paths, no network operations.

### Redirect Analysis

**Single redirect identified:**
- **Location**: `/app/main.py:103`
- **Code**: `RedirectResponse(url=f"/company/{company.id}/jobs", status_code=303)`
- **URL Construction**: Uses `company.id` from database authentication
- **company.id Source**: Integer primary key from `companies` table
- **User Control**: Indirect - user provides username/password, system retrieves company.id
- **URL Format**: Always relative path `/company/{integer}/jobs`
- **Attack Scenarios**:
  - ❌ Open Redirect: URL is relative, not absolute
  - ❌ SSRF: No outbound request made, only internal HTTP 303 redirect
  - ❌ Path Traversal: ID is integer type, not file path

**Verdict:** Redirect is safe - database-sourced integer ID, always relative path.

## 4. Secure by Design: Validated Components

The following components were analyzed and found to have no SSRF vulnerabilities due to secure architectural design:

| Component/Flow | Endpoint/File Location | Security Mechanism Implemented | Verdict |
|---|---|---|---|
| **Authentication Flow** | `POST /token` (main.py:93-105) | Accepts username/password only, performs local database lookup and bcrypt validation. No external authentication providers or OIDC discovery. | **SAFE** - No URL parameters, no outbound requests |
| **Job Listing Display** | `GET /company/{company_id}/jobs` (main.py:113-141) | Queries local SQLite database for job listings. All data sourced from database, no external API calls. | **SAFE** - Local database operations only |
| **Profile Edit Form** | `GET /edit_profile/{company_id}` (main.py:149-174) | Retrieves company data from local database and renders Jinja2 template. No external data sources. | **SAFE** - No outbound requests |
| **Profile Update** | `POST /edit_profile/{company_id}` (main.py:177-205) | Accepts `name` (string) and `level` (boolean) form fields. Updates local database via SQLAlchemy ORM. No URL parameters. | **SAFE** - No URL parameters, local database update only |
| **Health Check** | `GET /ping` (main.py:144-146) | Returns static JSON `{"ping": "pong"}`. No user input, no external requests. | **SAFE** - Static response, no SSRF potential |
| **Post-Login Redirect** | Line 103 (main.py) | Redirects to `/company/{company.id}/jobs` using database-derived integer ID. URL is always relative path. | **SAFE** - Database-sourced ID, relative URL only |
| **Startup Flag Loading** | Startup event (main.py:78-79) | Opens hardcoded local file "flag.txt". Executes once at startup, not per-request. | **SAFE** - Hardcoded filename, no user control, no network access |
| **Database Operations** | All CRUD operations (crud.py) | SQLAlchemy ORM queries against local SQLite database (`/app/test.db`). No remote database connections. | **SAFE** - Local file-based database only |
| **Template Rendering** | All Jinja2 templates | Server-side template rendering with no client-side AJAX or fetch operations. Templates include static CDN link for Bootstrap CSS (hardcoded, not user-controllable). | **SAFE** - No dynamic HTTP requests, static CDN links only |
| **JWT Token Operations** | Token generation/validation (main.py:39-56) | Local JWT encoding/decoding using python-jose library. No external JWKS fetching, no OIDC discovery endpoints. | **SAFE** - All JWT operations are local, no external token validation |

### Additional Security Validation

**Unused Dependencies:**
- **httpx==0.27.0**: Listed in requirements.txt but never imported or used
  - **Risk**: Phantom dependency increases supply chain attack surface
  - **Recommendation**: Remove from requirements.txt

**External Resource Loading:**
- **Bootstrap CSS**: Loaded from `https://stackpath.bootstrapcdn.com/bootstrap/4.5.2/css/bootstrap.min.css`
  - **User Control**: None (hardcoded URL in base.html template)
  - **SSRF Risk**: None (URL is not user-controllable, loaded by browser not server)
  - **Note**: No Subresource Integrity (SRI) checks implemented, but not relevant to SSRF

**WebSocket Analysis:**
- **Result**: No WebSocket endpoints or functionality
- **Evidence**: FastAPI app has no `@app.websocket()` decorators, no WebSocket libraries in requirements.txt

**Background Jobs:**
- **Result**: No background job processing or task queues
- **Evidence**: No Celery, RQ, or similar job queue libraries; no worker processes

## 5. Testing Methodology Applied

The following systematic analysis methodology was applied to identify potential SSRF vulnerabilities:

### 1. HTTP Client Usage Pattern Identification
- ✅ Searched for HTTP client imports: httpx, requests, urllib, aiohttp, http.client
- ✅ Searched for HTTP method calls: `.get()`, `.post()`, `.put()`, `.delete()`, `urlopen()`
- ✅ Examined all Python files for outbound request operations
- **Result**: Zero HTTP client usage detected

### 2. URL Parameter Analysis
- ✅ Examined all endpoint signatures for URL-like parameters
- ✅ Searched for parameter names: url, callback_url, webhook_url, redirect_to, return_url, next
- ✅ Reviewed form fields and query parameters
- **Result**: No URL parameters found in any endpoint

### 3. Protocol and Scheme Validation
- ✅ Checked for URL parsing and validation logic
- ✅ Searched for scheme restrictions (http://, https://, file://, etc.)
- **Result**: N/A - No URL processing functionality exists

### 4. Hostname and IP Address Validation
- ✅ Searched for IP address filtering logic
- ✅ Checked for internal IP range blocklists (RFC 1918 ranges, 169.254.0.0/16, etc.)
- **Result**: N/A - No hostname/IP validation needed (no outbound requests)

### 5. Port Restriction Analysis
- ✅ Searched for port specification in URLs
- ✅ Checked for port allowlisting/blocklisting
- **Result**: N/A - No outbound connection functionality

### 6. URL Parsing and Validation Bypass Techniques
- ✅ Checked for redirect following behavior
- ✅ Examined URL encoding/decoding logic
- **Result**: Single redirect uses database-sourced integer ID, not user-controllable URL

### 7. Request Modification and Headers
- ✅ Searched for header injection points
- ✅ Checked for custom header handling in outbound requests
- **Result**: N/A - No outbound requests exist

### 8. Response Handling and Information Disclosure
- ✅ Examined error messages for internal network information leakage
- ✅ Checked for response content returned to user
- **Result**: Application returns database content and rendered templates only

### 9. Backward Taint Analysis
- ✅ Traced all data flows from user input to potential SSRF sinks
- ✅ Identified sanitization points (N/A - no sinks exist)
- ✅ Documented source-to-sink paths (None found)
- **Result**: No SSRF sinks identified for backward taint analysis

### 10. Comprehensive Code Pattern Search

**Patterns searched (all returned zero matches):**
```
HTTP Client Operations:
- import httpx, import requests, import urllib, import aiohttp
- httpx.get, httpx.post, requests.get, requests.post
- urlopen, urlretrieve, urllib.request

URL Parameters:
- callback_url, webhook_url, redirect_to, return_url, next_url
- Form(...) with URL-like names

Socket Operations:
- import socket, socket.connect, socket.socket
- getaddrinfo, gethostbyname

External Integrations:
- webhook, api_key, oauth_provider, stripe, sendgrid
- boto3, azure, gcp (cloud SDKs)

File Fetching:
- fetch_url, download_file, get_remote_file
```

**Result**: Zero matches for SSRF-related patterns in application code.

## 6. Code Coverage Summary

**Files Analyzed:**
- `/app/main.py` (206 lines) - Main application endpoints
- `/app/crud.py` (45 lines) - Database operations
- `/app/models.py` (25 lines) - SQLAlchemy models
- `/app/schemas.py` (47 lines) - Pydantic schemas
- `/app/database.py` (11 lines) - Database connection
- `/app/templates/*.html` (4 template files) - Jinja2 templates
- `/app/requirements.txt` - Python dependencies

**Total Lines of Code Analyzed:** 334 lines (Python) + 4 templates

**Coverage:** 100% of application code reviewed for SSRF vulnerabilities

## 7. Conclusion

### Final Assessment

The FastAPI job listing platform (XBEN-005-24) running on http://localhost:41169/ has **ZERO SSRF attack surface**. The application is architecturally isolated from external network resources and performs no outbound HTTP requests in response to user input.

**Key Findings:**
1. ✅ **No HTTP client libraries used** - httpx is listed but never imported
2. ✅ **No URL parameters** - All parameters are strings, integers, or booleans
3. ✅ **No outbound requests** - All operations are local (database, templates, JWT)
4. ✅ **No external integrations** - No webhooks, APIs, or third-party services
5. ✅ **Safe redirect implementation** - Uses database-derived integer IDs, relative URLs only
6. ✅ **No file fetching from URLs** - Single local file read with hardcoded path

**Security Posture:** STRONG (for SSRF) - The application's self-contained architecture eliminates SSRF risks.

### Recommendations

**Immediate Actions:**
1. **Remove unused httpx dependency** from requirements.txt to reduce supply chain risk
2. **No SSRF remediation required** - No vulnerabilities exist

**Future Considerations:**
If outbound HTTP functionality is added in future releases, implement these SSRF controls:
- URL scheme allowlist (http/https only, block file://, gopher://, etc.)
- Domain/hostname allowlist (specific trusted domains)
- Block private IP ranges (10.0.0.0/8, 172.16.0.0/12, 192.168.0.0/16, 127.0.0.0/8, 169.254.169.254)
- Block localhost and loopback addresses
- Request timeouts (prevent slow loris attacks)
- Response size limits (prevent memory exhaustion)
- Disable redirect following or validate redirect destinations
- Use dedicated egress network interfaces with firewall rules

**Alternative Attack Vectors:**
While SSRF vulnerabilities are absent, the application has critical security issues in other areas:
- **Authentication**: Hardcoded JWT secret key ("a very secret key") enables token forgery
- **Authorization**: Missing ownership checks on POST /edit_profile enable IDOR
- **Privilege Escalation**: Users can modify their own `level` field to gain premium access
- **Recommendation**: Focus penetration testing efforts on authorization and privilege escalation vulnerabilities documented in the reconnaissance deliverable

---

**Report Generated:** 2025-01-08  
**Analyst:** SSRF Analysis Specialist  
**Target:** http://localhost:41169/ (FastAPI Job Listing Platform - XBEN-005-24)  
**Analysis Status:** COMPLETE  
**Vulnerabilities Found:** 0