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.
References7
- plugins.trac.wordpress.org/browser/kcaptcha/tags/1.0.1/admin/se…
- plugins.trac.wordpress.org/browser/kcaptcha/tags/1.0.1/admin/se…
- plugins.trac.wordpress.org/browser/kcaptcha/tags/1.0.1/admin/se…
- plugins.trac.wordpress.org/browser/kcaptcha/trunk/admin/setting…
- plugins.trac.wordpress.org/browser/kcaptcha/trunk/admin/setting…
- plugins.trac.wordpress.org/browser/kcaptcha/trunk/admin/setting…
- www.wordfence.com/threat-intel/vulnerabilities/id/a6c1c73b-76e3…
Metrics
- CVSS 3.1
-
4.3
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N - EPSS — exploit probability
- 0% percentile: 7 · as of 13 November 2026
- CWE
- CWE-352
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.