CVE-2024-9768 in Formidable Forms Plugin
Summary
by MITRE • 11/21/2024
The Formidable Forms WordPress plugin before 6.14.1 does not sanitise and escape some of its settings, which could allow high privilege users such as admin to perform Stored Cross-Site Scripting attacks even when the unfiltered_html capability is disallowed (for example in multisite setup).
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Analysis
by VulDB Data Team • 02/23/2025
The vulnerability identified as CVE-2024-9768 affects the Formidable Forms WordPress plugin version 6.14.1 and earlier, presenting a critical security risk through stored cross-site scripting flaws. This issue specifically targets high-privilege users including administrators who possess the capability to manipulate plugin settings despite the WordPress multisite environment's restrictions on unfiltered_html capabilities. The vulnerability stems from inadequate sanitization and escaping of user-provided input within the plugin's administrative interfaces, creating a persistent XSS attack vector that can compromise user sessions and potentially lead to full system compromise.
The technical flaw manifests in the plugin's failure to properly validate and sanitize configuration settings before storing them in the database. When administrators modify form settings or other plugin parameters through the WordPress admin dashboard, the input values are not adequately processed to remove or escape potentially malicious script content. This oversight allows attackers with administrative privileges to inject malicious JavaScript code into plugin settings that persists in the database and executes whenever affected pages are loaded. The vulnerability is particularly concerning in multisite environments where the unfiltered_html capability is typically restricted to prevent XSS attacks, yet the flaw allows bypassing these protections through the plugin's settings handling mechanisms.
The operational impact of this vulnerability extends beyond simple script execution, as it enables attackers to perform session hijacking, data theft, and potentially gain unauthorized access to sensitive system information. Stored XSS attacks in administrative interfaces pose significant risks because they can compromise not only the targeted user's session but also potentially affect other users who view the compromised pages. Attackers could inject malicious scripts that steal cookies, redirect users to phishing sites, or perform unauthorized actions on behalf of the compromised administrator. The persistence of these attacks makes them particularly dangerous as they continue to execute until manually removed from the database, potentially affecting multiple users over extended periods.
Mitigation strategies for CVE-2024-9768 require immediate plugin updates to version 6.14.1 or later, which contain the necessary sanitization and escaping fixes. Organizations should also implement additional security measures including regular security audits of plugin configurations, monitoring of administrative interfaces for unauthorized changes, and maintaining up-to-date security scanning tools. The vulnerability aligns with CWE-79 (Cross-Site Scripting) and maps to ATT&CK techniques including T1059.007 (Command and Scripting Interpreter: JavaScript) and T1566.001 (Phishing: Spearphishing Attachment) as attackers may leverage the compromised administrative sessions to conduct further attacks. System administrators should also consider implementing web application firewalls and restricting administrative access through additional authentication measures to reduce the attack surface.