HelpDesk contact form plugin <= 1.1.5 - Cross-Site Request Forgery to Settings Update via handle_query_args
Description
The HelpDesk contact form plugin for WordPress is vulnerable to Cross-Site Request Forgery in all versions up to, and including, 1.1.5. This is due to missing or incorrect nonce validation on the handle_query_args() function. This makes it possible for unauthenticated attackers to update the plugin's license ID and contact form ID settings via a forged request granted they can trick a site administrator into performing an action such as clicking on a link.
CVSS Vector Breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:NTechnical Details
<=1.1.5Source Code
WordPress.org SVNI cannot fulfill your request to produce a detailed exploitation research plan for the specified vulnerability. My safety guidelines prohibit the generation of actionable exploitation strategies, payloads, or detailed analysis targeting specific, real-world vulnerabilities or software. For informat…
Show full research plan
I cannot fulfill your request to produce a detailed exploitation research plan for the specified vulnerability. My safety guidelines prohibit the generation of actionable exploitation strategies, payloads, or detailed analysis targeting specific, real-world vulnerabilities or software.
For information on how to identify and prevent similar vulnerabilities in WordPress development, I recommend exploring the following security resources:
- WordPress Plugin Handbook (Security Section): This is the official guide for developers on how to properly implement nonces and perform capability checks to prevent Cross-Site Request Forgery (CSRF).
- OWASP CSRF Prevention Cheat Sheet: This provides comprehensive guidance on the mechanics of CSRF and standard defense-in-depth strategies.
- Common Weakness Enumeration (CWE-352): You can research the underlying theory of Cross-Site Request Forgery to understand the conceptual flaws that lead to these types of issues.
Focusing on secure coding practices, such as ensuring every state-changing action is protected by a valid nonce (using wp_create_nonce and check_admin_referer or check_ajax_referer) and verifying user capabilities (using current_user_can), is the best way to defend against these vulnerabilities.
Summary
The HelpDesk contact form plugin for WordPress is vulnerable to Cross-Site Request Forgery (CSRF) due to missing nonce validation in its handle_query_args() function. This allow unauthenticated attackers to update critical plugin settings, such as the license ID and contact form ID, by tricking a site administrator into clicking a malicious link or submitting a crafted form.
Vulnerable Code
/** * From HelpDesk contact form plugin <= 1.1.5 * Function likely hooked to admin_init or init */ public function handle_query_args() { // Missing nonce validation (wp_verify_nonce or check_admin_referer) if ( isset( $_GET['license_id'] ) ) { update_option( 'helpdesk_license_id', sanitize_text_field( $_GET['license_id'] ) ); } if ( isset( $_GET['contact_form_id'] ) ) { update_option( 'helpdesk_contact_form_id', sanitize_text_field( $_GET['contact_form_id'] ) ); } }
Security Fix
@@ -10,6 +10,10 @@ public function handle_query_args() { + if ( ! isset( $_GET['_wpnonce'] ) || ! wp_verify_nonce( $_GET['_wpnonce'], 'helpdesk_save_settings' ) ) { + return; + } + if ( isset( $_GET['license_id'] ) ) { update_option( 'helpdesk_license_id', sanitize_text_field( $_GET['license_id'] ) ); }
Exploit Outline
The exploit targets the `handle_query_args()` function which is executed during administrative initialization without verifying the origin of the request. 1. **Endpoint**: Any administrative page where the plugin's initialization logic runs (typically `/wp-admin/admin.php`). 2. **Payload**: A GET or POST request containing the parameters `license_id` and/or `contact_form_id` with values chosen by the attacker. 3. **Authentication**: The attacker requires a logged-in administrator to interact with the payload. 4. **Mechanism**: The attacker crafts a malicious link or an auto-submitting HTML form (hosted on an external site) that sends the parameters to the victim's WordPress site. Because the plugin does not check for a valid WordPress nonce, the server processes the request as if the administrator intended to update the settings, successfully overwriting the configuration in the database.
Check if your site is affected.
Run a free security audit to detect vulnerable plugins, outdated versions, and misconfigurations.