CVE-2024-47389 Overview
CVE-2024-47389 is a reflected cross-site scripting (XSS) vulnerability in the Basix NEX-Forms WordPress plugin (nex-forms-express-wp-form-builder). The flaw stems from improper neutralization of user-supplied input during web page generation, classified under [CWE-79]. All versions of NEX-Forms up to and including 8.7.3 are affected. Attackers can craft malicious URLs that, when clicked by an authenticated user, execute arbitrary JavaScript in the victim's browser session. The vulnerability requires user interaction but no privileges, and its scope change indicates impact beyond the vulnerable component.
Critical Impact
Successful exploitation allows attackers to execute arbitrary JavaScript in a victim's browser context, enabling session theft, credential harvesting, and unauthorized actions against WordPress sites running NEX-Forms 8.7.3 or earlier.
Affected Products
- Basix NEX-Forms WordPress plugin (nex-forms-express-wp-form-builder)
- All versions from n/a through 8.7.3
- WordPress installations with the plugin active
Discovery Timeline
- 2024-10-05 - CVE-2024-47389 published to NVD
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2024-47389
Vulnerability Analysis
The vulnerability is a reflected XSS flaw in the NEX-Forms plugin's request handling. The plugin accepts input parameters and reflects them back into rendered HTML output without adequate sanitization or output encoding. When an attacker delivers a specially crafted URL, the injected payload becomes part of the response and executes in the victim's browser.
Reflected XSS in WordPress plugin contexts is particularly effective because administrators often interact with plugin pages while authenticated. Payloads executing in that session can perform any action the administrator can perform, including creating new admin accounts, modifying content, or exfiltrating data.
The scope-changed impact indicates the injected script can affect resources beyond the initial vulnerable component, such as other browser tabs, iframes, or WordPress subsystems sharing the origin.
Root Cause
The root cause is missing or insufficient input neutralization in one or more request parameters processed by the NEX-Forms plugin. User-controlled data flows into HTML output without escaping via functions such as esc_html(), esc_attr(), or wp_kses(). This omission allows attacker-supplied <script> tags or event-handler attributes to render as executable code.
Attack Vector
Exploitation requires an attacker to deliver a crafted URL to a target user, typically through phishing email, malicious link on a controlled site, or social engineering. The victim must be authenticated to the WordPress instance and click the link. The plugin then reflects the payload into the response, and the browser executes the injected JavaScript in the WordPress origin.
The exploitation flow: the attacker identifies a vulnerable parameter, embeds a JavaScript payload into a URL targeting the WordPress site, and lures an authenticated user to click it. The plugin processes the request, echoes the payload into the page, and the browser executes it. See the Patchstack Vulnerability Report for advisory details.
Detection Methods for CVE-2024-47389
Indicators of Compromise
- Web server access logs containing NEX-Forms plugin URLs with encoded <script>, javascript:, onerror=, or onload= payloads in query parameters
- Unexpected administrator account creation or privilege changes in the WordPress wp_users table
- Outbound requests from browsers loading NEX-Forms pages to attacker-controlled domains
- Suspicious WordPress REST API calls originating from admin sessions shortly after clicking external links
Detection Strategies
- Deploy a web application firewall (WAF) rule to inspect requests to nex-forms-express-wp-form-builder endpoints for XSS payload signatures
- Monitor referrer headers for authenticated admin sessions originating from external, untrusted domains
- Review WordPress audit logs for unexpected content modifications tied to admin sessions following URL clicks
Monitoring Recommendations
- Enable verbose HTTP access logging on the WordPress front end and retain logs for correlation
- Configure browser-based Content Security Policy (CSP) reporting to capture blocked inline script executions
- Alert on user-agent, IP, and session anomalies for authenticated administrator accounts
How to Mitigate CVE-2024-47389
Immediate Actions Required
- Update the NEX-Forms plugin to a version above 8.7.3 as soon as the vendor releases a fix
- Audit WordPress administrator and editor accounts for unauthorized additions or role changes
- Rotate credentials and session tokens for any user who may have clicked suspicious NEX-Forms URLs
- Enforce a strict Content Security Policy that blocks inline scripts and restricts script sources
Patch Information
Refer to the Patchstack Vulnerability Report for the current patched version and vendor advisory status. Apply plugin updates through the WordPress admin dashboard or via WP-CLI. Versions through 8.7.3 remain vulnerable.
Workarounds
- Deactivate the NEX-Forms plugin until a patched version is installed if immediate updating is not possible
- Deploy WAF rules to filter requests containing XSS payload patterns targeting NEX-Forms endpoints
- Restrict administrative access to the WordPress backend through IP allowlisting or VPN requirements
- Train administrators to avoid clicking external links while authenticated to the WordPress admin panel
# Configuration example: update NEX-Forms via WP-CLI once a patched version is available
wp plugin update nex-forms-express-wp-form-builder
wp plugin status nex-forms-express-wp-form-builder
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
