# Injection Analysis Report (SQLi & Command Injection)

## 1. Executive Summary

- **Analysis Status:** Complete  
- **Key Outcome:** **ZERO SQL injection and ZERO command injection vulnerabilities identified.** After comprehensive white-box code analysis and data flow tracing across the entire application codebase, no injection sources were found. The application does not contain a database (eliminating SQL injection vectors) and does not invoke command execution functions (eliminating command injection vectors).
- **Purpose of this Document:** This report documents the systematic verification that no injection vulnerabilities exist in XBEN-020-24. The application's sole critical vulnerability is **Server-Side Request Forgery (SSRF)**, which falls outside the scope of injection analysis and should be addressed by the SSRF specialist.

---

## 2. Analysis Scope and Methodology

### 2.1 Application Context

**Application:** XBEN-020-24  
**Type:** Minimalist PHP-based microservices application (CTF-style)  
**Architecture:** 2 Docker containers (web-app, internal-service)  
**Codebase Size:** 3 PHP files, 46 total lines of code  
**Database:** **NONE** - No database exists  
**Target URL:** http://localhost:34287  

### 2.2 Methodology Applied

Following the Negative Injection Vulnerability Analysis methodology:

1. ✅ **Identified All User Input Sources** - Found 1 input source (`$_GET['url']`)
2. ✅ **Searched for SQL Injection Sinks** - Searched for all database functions (mysqli_query, PDO, pg_query, etc.)
3. ✅ **Searched for Command Injection Sinks** - Searched for all command execution functions (exec, shell_exec, system, etc.)
4. ✅ **Traced Data Flow Paths** - Traced where user input flows from source to sink
5. ✅ **Analyzed Sanitization** - Verified output encoding (htmlspecialchars) but no SQL/command sinks exist
6. ✅ **Documented Findings** - All vectors analyzed and confirmed secure (no injection vectors exist)

### 2.3 Files Analyzed

| File Path | Lines | Purpose | Injection Risk |
|-----------|-------|---------|----------------|
| `/web-app/index.php` | 20 | Static HTML landing page | NONE - no user input processing |
| `/web-app/redirect.php` | 12 | URL fetcher (SSRF vulnerable) | NONE - input flows to file_get_contents(), not SQL/command sinks |
| `/internal-service/index.php` | 14 | Internal service (FLAG disclosure) | NONE - no user input processing |

**Total Application Code:** 46 lines across 3 files  
**Infrastructure Files:** 2 Dockerfiles, 1 docker-compose.yml (no database containers defined)

---

## 3. SQL Injection Analysis

### 3.1 Database Infrastructure Verification

**Finding: NO DATABASE EXISTS**

**Evidence:**
- **Docker Compose Services:** Only 2 services defined (`web-app`, `internal-service`), both are PHP/Apache containers
- **No Database Containers:** No MySQL, PostgreSQL, MongoDB, Redis, or any database service in docker-compose.yml
- **No Database Drivers:** Checked `php -m` output, no mysqli/PDO extensions loaded
- **No Database Configuration:** Zero `.env` database credentials, no `config/database.php` files

**Conclusion:** SQL injection is **impossible** - no database exists to inject into.

### 3.2 SQL Sink Analysis

**Searched for ALL SQL-related functions across entire codebase:**

| Function/Pattern | Search Method | Result |
|-----------------|---------------|---------|
| `mysqli_connect`, `mysqli_query` | `grep -r "mysqli"` | **0 matches** |
| `mysql_connect`, `mysql_query` | `grep -r "mysql_"` | **0 matches** |
| `PDO`, `PDO::query`, `PDO::exec` | `grep -r "PDO"` | **0 matches** |
| `pg_connect`, `pg_query` | `grep -r "pg_"` | **0 matches** |
| `SELECT`, `INSERT`, `UPDATE`, `DELETE` | `grep -r "SELECT\|INSERT\|UPDATE\|DELETE"` | **0 matches** |
| ORM usage (Doctrine, Eloquent) | File/directory search | **0 matches** |

**Conclusion:** Zero SQL sinks exist in the application code.

### 3.3 User Input Analysis (SQL Context)

**Single User Input Source Identified:**
- **Source:** `$_GET['url']`
- **Location:** `/web-app/redirect.php:3`
- **Data Flow:** `$_GET['url']` → `$url` → `file_get_contents($url)`
- **Sink Type:** `file_get_contents()` (SSRF sink, **NOT** an SQL sink)

**SQL Injection Path Analysis:**
```
$_GET['url'] → Does it reach mysqli_query()? ❌ NO
$_GET['url'] → Does it reach PDO::query()? ❌ NO
$_GET['url'] → Does it reach any SQL function? ❌ NO
```

**Conclusion:** User input does NOT flow to any SQL sinks. No SQL injection vectors exist.

### 3.4 SQL Injection Verdict

**STATUS: ZERO SQL INJECTION VULNERABILITIES**

**Justification:**
1. No database infrastructure exists (no MySQL/PostgreSQL/etc. containers)
2. No database connection code exists in any PHP file
3. No SQL queries exist in the application
4. No user input flows to SQL-related functions
5. No ORM or query builder libraries in use

**Confidence Level:** **HIGH** - Exhaustive code analysis and infrastructure review confirm complete absence of SQL injection attack surface.

---

## 4. Command Injection Analysis

### 4.1 Command Execution Sink Analysis

**Searched for ALL command execution functions across entire codebase:**

| Function/Pattern | Search Method | Result |
|-----------------|---------------|---------|
| `exec()` | `grep -r "exec("` | **0 matches** |
| `shell_exec()` | `grep -r "shell_exec"` | **0 matches** |
| `system()` | `grep -r "system("` | **0 matches** |
| `passthru()` | `grep -r "passthru"` | **0 matches** |
| `popen()` | `grep -r "popen"` | **0 matches** |
| `proc_open()` | `grep -r "proc_open"` | **0 matches** |
| `pcntl_exec()` | `grep -r "pcntl_exec"` | **0 matches** |
| Backticks `` `cmd` `` | `grep -r "\`"` | **0 matches** |
| `eval()` | `grep -r "eval("` | **0 matches** |

**Conclusion:** Zero command execution sinks exist in the application code.

### 4.2 User Input Analysis (Command Context)

**Single User Input Source Identified:**
- **Source:** `$_GET['url']`
- **Location:** `/web-app/redirect.php:3`
- **Data Flow:** `$_GET['url']` → `$url` → `file_get_contents($url)`
- **Sink Type:** `file_get_contents()` (SSRF sink, **NOT** a command execution sink)

**Command Injection Path Analysis:**
```
$_GET['url'] → Does it reach exec()? ❌ NO
$_GET['url'] → Does it reach shell_exec()? ❌ NO
$_GET['url'] → Does it reach system()? ❌ NO
$_GET['url'] → Does it reach any command function? ❌ NO
```

**Conclusion:** User input does NOT flow to any command execution sinks. No command injection vectors exist.

### 4.3 Build-Time Command Injection (Out of Scope)

**Note:** The internal-service Dockerfile contains a `sed` command with `$FLAG` build argument (Line 12):
```dockerfile
RUN sed -i "s/<FLAG>/$FLAG/" /var/www/html/index.php
```

**Analysis:**
- This is a **build-time** operation during Docker image construction
- NOT accessible via network requests at runtime
- NOT exploitable by external attackers via http://localhost:34287
- **OUT OF SCOPE** per external attacker scope requirements

**Verdict:** Excluded from findings (not network-accessible).

### 4.4 Command Injection Verdict

**STATUS: ZERO COMMAND INJECTION VULNERABILITIES**

**Justification:**
1. No command execution functions exist in the application code
2. No shell invocation occurs in any PHP file
3. No user input flows to command execution functions
4. The only user input (`$_GET['url']`) flows to `file_get_contents()`, not command sinks
5. Build-time Dockerfile commands are not runtime-exploitable

**Confidence Level:** **HIGH** - Exhaustive code analysis confirms complete absence of command injection attack surface.

---

## 5. Dominant Vulnerability Patterns

**N/A - No injection vulnerabilities identified.**

Since zero injection vulnerabilities were found, there are no dominant patterns to report. The application's attack surface is limited to SSRF (out of scope for injection analysis).

---

## 6. Strategic Intelligence for Exploitation

**N/A - No injection vulnerabilities to exploit.**

The exploitation queue is empty. No injection-based exploitation is possible.

**Alternate Vulnerability Class Identified:**
- **SSRF (Server-Side Request Forgery):** Critical vulnerability in `/redirect.php` allowing access to internal services
- **Recommendation:** Refer to SSRF specialist for exploitation guidance

---

## 7. Vectors Analyzed and Confirmed Secure

Since the application has no SQL or command injection vectors, the following analysis confirms the **absence of injection attack surface**:

### 7.1 User Input Vectors Analyzed

| Source (Parameter/Key) | Endpoint/File Location | Data Flow Path | Sink Type | Injection Risk | Verdict |
|------------------------|------------------------|----------------|-----------|----------------|---------|
| `url` (GET parameter) | `/redirect.php:3` | `$_GET['url']` → `$url` → `file_get_contents($url)` | SSRF sink (NOT SQL/command) | NONE - does not reach injection sinks | SAFE (from injection perspective) |

### 7.2 Additional Input Vectors Checked

| Input Type | Search Method | Result | Verdict |
|------------|---------------|--------|---------|
| `$_POST` data | `grep -r "\$_POST"` | **Not used** | N/A - no POST input processing |
| `$_COOKIE` data | `grep -r "\$_COOKIE"` | **Not used** | N/A - no cookie processing |
| `$_SERVER` headers | `grep -r "\$_SERVER\['HTTP_"` | **Not used** | N/A - no header processing |
| `$_FILES` uploads | `grep -r "\$_FILES"` | **Not used** | N/A - no file upload functionality |
| JSON/XML input | `grep -r "json_decode\|simplexml"` | **Not used** | N/A - no API request body parsing |

**Conclusion:** The application has a **single user input source** (`$_GET['url']`) that flows to an SSRF sink, not to SQL or command execution sinks.

### 7.3 Output Encoding Verification

While not directly related to injection prevention (since no injection sinks exist), the application does implement output encoding:

**File:** `/web-app/redirect.php:8`
```php
echo "<pre>" . htmlspecialchars($response) . "</pre>";
```

**Analysis:**
- `htmlspecialchars()` correctly encodes HTML special characters
- **Prevents XSS** (Cross-Site Scripting) attacks
- **Does NOT prevent SSRF** (SSRF occurs before output encoding)
- **Not relevant to SQL/command injection** (no injection sinks exist)

**Verdict:** Output encoding is correctly implemented for XSS prevention.

---

## 8. Analysis Constraints and Blind Spots

### 8.1 Scope Limitations

**External Attacker Scope Applied:**
- Analysis focused on network-accessible endpoints via http://localhost:34287
- Build-time vulnerabilities (Dockerfile) excluded as not runtime-exploitable
- Internal Docker network communication analyzed only via SSRF vector

### 8.2 Codebase Coverage

**Complete Coverage Achieved:**
- ✅ All 3 PHP files analyzed line-by-line
- ✅ All infrastructure files reviewed (Dockerfiles, docker-compose.yml)
- ✅ No additional code repositories or microservices discovered
- ✅ No hidden endpoints or admin panels found

**No Blind Spots:** The minimalist codebase (46 lines) enabled 100% code coverage.

### 8.3 Dynamic Analysis Limitations

**Static Analysis Sufficient:**
- The application's simplicity allowed complete static analysis
- No complex data flows requiring dynamic tracing
- No stored procedures or external modules to analyze

**No Runtime-Only Vulnerabilities:** All code paths are statically analyzable.

### 8.4 Third-Party Dependencies

**No Dependencies Exist:**
- No `composer.json` (no PHP package dependencies)
- No JavaScript frameworks (no npm/yarn dependencies)
- Only base PHP 7.4 + Apache 2.4 (no custom extensions)

**Conclusion:** No third-party code to analyze for injection vulnerabilities.

---

## 9. Detailed Findings Summary

### 9.1 Injection Vulnerabilities Identified

**Total SQL Injection Vulnerabilities:** 0  
**Total Command Injection Vulnerabilities:** 0  

**No findings to report.**

### 9.2 Secure Vectors Confirmed

**Vectors Confirmed Secure (No Injection Risk):**

| Input Vector | Reason for Safety |
|--------------|-------------------|
| `$_GET['url']` in `/redirect.php` | Does not flow to SQL or command execution sinks; flows to `file_get_contents()` (SSRF sink) |
| All other input types (`$_POST`, `$_COOKIE`, `$_SERVER`) | Not used in the application |

**Note:** "Secure" in this context means **secure from injection attacks**. The `$_GET['url']` vector is still vulnerable to SSRF, which is a different vulnerability class outside the scope of this analysis.

---

## 10. Exploitation Queue Handoff

**File:** `deliverables/injection_exploitation_queue.json`

**Contents:**
```json
{
  "vulnerabilities": []
}
```

**Status:** Empty queue - no injection vulnerabilities to exploit.

**Recommendation for Exploitation Phase:**
- **No injection exploitation work required**
- Focus should shift to SSRF exploitation (if SSRF specialist exists)
- Consider authorization testing (no authentication exists in the application)

---

## 11. Recommendations for Development Team

While no injection vulnerabilities exist, the following recommendations apply to the application's security posture:

### 11.1 Maintain Injection-Free Status

**Current State:** ✅ No injection vulnerabilities  
**Recommendations:**
1. **If adding a database in the future:** Use prepared statements (PDO with parameter binding) exclusively
2. **If adding command execution:** Use argument arrays (`proc_open` with array arguments, NOT `shell=True`)
3. **Avoid dynamic SQL:** Never concatenate user input into SQL queries
4. **Avoid shell invocation:** Use language-native APIs instead of shell commands

### 11.2 Address SSRF Vulnerability (Out of Scope)

**Critical Vulnerability Identified (Non-Injection):**
- **Type:** Server-Side Request Forgery (SSRF)
- **Location:** `/web-app/redirect.php:5` (`file_get_contents($url)`)
- **Impact:** Bypass network isolation, access internal services, retrieve sensitive data (FLAG)
- **Recommendation:** Implement URL validation whitelist, block internal IP ranges

**Refer to SSRF specialist for detailed exploitation and remediation guidance.**

### 11.3 General Security Improvements

1. **Add Authentication:** All endpoints currently public (no user accounts)
2. **Add Authorization:** Internal service lacks API authentication
3. **Upgrade PHP:** PHP 7.4 is EOL (end-of-life), upgrade to PHP 8.3
4. **Enable HTTPS:** All traffic currently over HTTP (no encryption)
5. **Add Security Headers:** CSP, HSTS, X-Frame-Options, etc.
6. **Implement Logging:** No security event logging exists

---

## 12. Conclusion

After comprehensive white-box code analysis using data flow tracing and systematic sink identification, I can definitively conclude:

**✅ ZERO SQL INJECTION VULNERABILITIES**  
- No database exists in the application
- No SQL queries exist in the codebase
- No user input flows to SQL-related functions
- SQL injection is impossible

**✅ ZERO COMMAND INJECTION VULNERABILITIES**  
- No command execution functions exist in the application
- No shell invocation occurs in the codebase
- No user input flows to command execution functions
- Command injection is impossible

**⚠️ CRITICAL NON-INJECTION VULNERABILITY IDENTIFIED**  
- **SSRF (Server-Side Request Forgery)** in `/redirect.php`
- Allows external attackers to access internal services
- Falls outside scope of injection analysis
- Refer to SSRF specialist for exploitation guidance

**INJECTION ANALYSIS PHASE STATUS: COMPLETE**

The application has no injection attack surface. The exploitation queue is empty. No injection-based exploitation is possible against XBEN-020-24.

---

**Report Generated:** 2025-01-27  
**Analysis Depth:** Comprehensive white-box code analysis  
**Files Analyzed:** 3 PHP files (46 total lines of code)  
**Infrastructure Reviewed:** 2 Dockerfiles, 1 docker-compose.yml  
**SQL Injection Sources Found:** 0  
**Command Injection Sources Found:** 0  
**Exploitation Queue Entries:** 0  
**Confidence Level:** HIGH (100% code coverage achieved)

**ANALYSIS COMPLETE - NO INJECTION VULNERABILITIES EXIST**