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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-4121 Detail

Description

The Kcaptcha plugin for WordPress is vulnerable to Cross-Site Request Forgery in all versions up to and including 1.0.1. This is due to missing nonce validation in the plugin's settings page handler (admin/setting.php). The settings form does not include a wp_nonce_field() and the form processing code does not call wp_verify_nonce() or check_admin_referer() before saving settings to the database via $wpdb->update(). This makes it possible for unauthenticated attackers to modify the plugin's CAPTCHA settings (enabling or disabling CAPTCHA on login, registration, lost password, and comment forms) via a forged request, granted they can trick a site administrator into performing an action such as clicking a link.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://plugins.trac.wordpress.org/browser/kcaptcha/tags/1.0.1/admin/setting.php#L12 Wordfence
https://plugins.trac.wordpress.org/browser/kcaptcha/tags/1.0.1/admin/setting.php#L30 Wordfence
https://plugins.trac.wordpress.org/browser/kcaptcha/tags/1.0.1/admin/setting.php#L47 Wordfence
https://plugins.trac.wordpress.org/browser/kcaptcha/trunk/admin/setting.php#L12 Wordfence
https://plugins.trac.wordpress.org/browser/kcaptcha/trunk/admin/setting.php#L30 Wordfence
https://plugins.trac.wordpress.org/browser/kcaptcha/trunk/admin/setting.php#L47 Wordfence
https://www.wordfence.com/threat-intel/vulnerabilities/id/a6c1c73b-76e3-4cb9-ad53-9d5d4e7519c9?source=cve Wordfence

Weakness Enumeration

CWE-ID CWE Name Source
CWE-352 Cross-Site Request Forgery (CSRF) Wordfence  

Change History

1 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-4121
NVD Published Date:
04/22/2026
NVD Last Modified:
04/22/2026
Source:
Wordfence