EUVD-2023-28261 Technical Analysis Report

Executive Summary

EUVD-2023-28261 (CVE-2023-24202) represents a critical severity Local File Inclusion (LFI) vulnerability in Raffle Draw System v1.0. With a CVSS 3.1 base score of 9.8, this vulnerability poses an immediate and severe threat to affected systems, enabling unauthenticated remote attackers to access sensitive files and potentially achieve remote code execution.

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1. Vulnerability Assessment and Severity Evaluation

Severity Classification

• CVSS 3.1 Base Score: 9.8 (Critical)
• Attack Vector (AV:N): Network-based exploitation
• Attack Complexity (AC:L): Low complexity, minimal skill required
• Privileges Required (PR:N): No authentication needed
• User Interaction (UI:N): No user interaction required
• Scope (S:U): Unchanged
• Impact Metrics: High confidentiality, integrity, and availability impact (C:H/I:H/A:H)

Risk Assessment

This vulnerability represents a maximum severity threat due to:

• Unauthenticated exploitation: No credentials required
• Remote accessibility: Exploitable over network connections
• Trivial exploitation: Low technical barrier for attackers
• Complete system compromise potential: Can lead to full server takeover
• Public exploit availability: Documented proof-of-concept exists on GitHub

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2. Attack Vectors and Exploitation Methods

Vulnerability Mechanism

The LFI vulnerability exists in the page parameter of index.php, allowing attackers to manipulate file path references to access arbitrary files on the server.

Exploitation Techniques

Basic LFI Exploitation

http://[target]/index.php?page=../../../../etc/passwd
http://[target]/index.php?page=../../../../etc/shadow
http://[target]/index.php?page=../../../../var/www/html/config.php

Advanced Attack Scenarios

1. Configuration File Disclosure

• Access database credentials from configuration files
• Extract API keys and authentication tokens
• Retrieve application secrets

2. Log File Poisoning → Remote Code Execution

Step 1: Inject PHP code into log files via User-Agent or other headers
Step 2: Include the poisoned log file via LFI
Step 3: Execute arbitrary PHP code

3. Session File Manipulation

• Access PHP session files (typically in /tmp or /var/lib/php/sessions)
• Extract session tokens for privilege escalation

4. Wrapper-Based Exploitation

php://filter/convert.base64-encode/resource=config.php
data://text/plain;base64,[base64_encoded_php_code]
expect://whoami

5. Remote Code Execution Chain

• Upload malicious file via another vector
• Use LFI to include and execute the uploaded file
• Establish persistent backdoor access

Attack Complexity

• Skill Level Required: Novice to Intermediate
• Tools Required: Web browser or basic HTTP client (curl, wget)
• Time to Exploit: Minutes
• Detection Difficulty: Moderate (without proper logging/monitoring)

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3. Affected Systems and Software Versions

Confirmed Affected Software

• Product: Raffle Draw System
• Affected Version: v1.0
• Platform: PHP-based web application
• Source: SourceCodester (free source code distribution)

Deployment Context

This application is typically deployed in:

• Small to medium business environments
• Event management scenarios
• Educational/demonstration environments
• LAMP/LEMP stack configurations (Linux, Apache/Nginx, MySQL, PHP)

Potential Exposure

• Organizations using free/open-source raffle systems
• Entities that downloaded from SourceCodester platform
• Development/testing environments with production data
• Unpatched systems deployed before February 2023

Infrastructure at Risk

• Web servers: Apache, Nginx running PHP
• Operating Systems: Linux distributions (Ubuntu, CentOS, Debian)
• Database systems: MySQL/MariaDB (credentials accessible via LFI)
• Backend systems: Potentially accessible through configuration file disclosure

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4. Recommended Mitigation Strategies

Immediate Actions (Priority 1 - Within 24 Hours)

1. System Isolation

• Immediately disconnect affected systems from public internet
• Place behind WAF with strict input validation rules
• Implement network segmentation to limit lateral movement

2. Input Validation Implementation

// Whitelist approach for page parameter
$allowed_pages = ['home', 'about', 'contact', 'results'];
$page = isset($_GET['page']) ? $_GET['page'] : 'home';

if (!in_array($page, $allowed_pages)) {
    $page = 'home';
}

include($page . '.php');

3. Emergency Patching

• Remove or disable the vulnerable page parameter functionality
• Implement strict path traversal prevention:

$page = basename($_GET['page']); // Remove directory components
$page = str_replace(['../', '..\\'], '', $page); // Strip traversal sequences

Short-Term Mitigations (Priority 2 - Within 1 Week)

1. Web Application Firewall (WAF) Rules

# ModSecurity/WAF rules
SecRule ARGS:page "@contains ../" "id:1001,deny,status:403"
SecRule ARGS:page "@contains /etc/" "id:1002,deny,status:403"
SecRule ARGS:page "@rx (?:etc/passwd|proc/self)" "id:1003,deny,status:403"

2. PHP Configuration Hardening

; php.ini security settings
open_basedir = /var/www/html:/tmp
allow_url_include = Off
allow_url_fopen = Off
disable_functions = exec,passthru,shell_exec,system,proc_open,popen

3. File System Permissions

# Restrict file access
chmod 640 /etc/passwd
chmod 600 /etc/shadow
chmod 640 config.php
chown root:www-data config.php

Long-Term Solutions (Priority 3 - Within 1 Month)

1. Application Replacement

• Migrate to actively maintained, security-audited alternatives
• Conduct vendor security assessment before deployment
• Implement secure development lifecycle practices

2. Secure Code Refactoring

// Implement proper MVC routing
class Router {
    private $routes = [
        'home' => 'controllers/HomeController.php',
        'results' => 'controllers/ResultsController.php'
    ];
    
    public function route($page) {
        if (!isset($this->routes[$page])) {
            return $this->routes['home'];
        }
        
        $controller = $this->routes[$page];
        if (file_exists($controller)) {
            require_once $controller;
        }
    }
}

3. Security Monitoring Implementation

• Deploy intrusion detection systems (IDS/IPS)
• Implement comprehensive logging:

// Log all page parameter access attempts
error_log("Page access attempt: " . $_SERVER['REMOTE_ADDR'] . 
          " - Page: " . $_GET['page'] . 
          " - User-Agent: " . $_SERVER['HTTP_USER_AGENT']);

4. Regular Security Assessments

• Quarterly vulnerability scanning
• Annual penetration testing
• Code review for all third-party components

Defense-in-Depth Measures

1. Network Layer

• Implement geo-blocking if appropriate
• Rate limiting on application endpoints
• DDoS protection services

2. Application Layer

• Content Security Policy (CSP) headers
• Strict input validation and output encoding
• Principle of least privilege for file access

3. Monitoring and Detection

# SIEM alert rules for LFI attempts
alert tcp any any -> $WEB_SERVERS $HTTP_PORTS (
    msg:"Possible LFI attempt - path travers