ksolves Kcaptcha Plugin up to 1.0.1 on WordPress admin/setting.php wp_nonce_field cross-site request forgery

Summaryinfo

A vulnerability described as problematic has been identified in ksolves Kcaptcha Plugin up to 1.0.1 on WordPress. This vulnerability affects the function wp_nonce_field of the file admin/setting.php. Such manipulation leads to cross-site request forgery. This vulnerability is referenced as CVE-2026-4121. It is possible to launch the attack remotely. No exploit is available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability was found in ksolves Kcaptcha Plugin up to 1.0.1 on WordPress and classified as problematic. Affected by this issue is the function wp_nonce_field of the file admin/setting.php. The manipulation with an unknown input leads to a cross-site request forgery vulnerability. Using CWE to declare the problem leads to CWE-352. The web application does not, or can not, sufficiently verify whether a well-formed, valid, consistent request was intentionally provided by the user who submitted the request. Impacted is integrity. CVE summarizes:

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.

The weakness was published by Muhammad Afnaan. The advisory is available at wordfence.com. This vulnerability is handled as CVE-2026-4121 since 03/13/2026. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. Successful exploitation requires user interaction by the victim. Technical details are known, but there is no available exploit.

By approaching the search of inurl:admin/setting.php it is possible to find vulnerable targets with Google Hacking.

Upgrading to version 1.0.1 eliminates this vulnerability.

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Productinfo

Type

• WordPress Plugin

Vendor

• ksolves

Name

• Kcaptcha Plugin

Version

• 1.0.0
• 1.0.1

CPE 2.3info

• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒

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