Executive Summary

The vulnerability in the HTML Forms – Simple WordPress Forms Plugin (up to version 1.6.0) is an Unauthenticated Stored Cross-Site Scripting (XSS) issue. It occurs because the plugin does not properly sanitize fabricated file upload field metadata before displaying it in the WordPress admin dashboard. This allows unauthenticated attackers to inject arbitrary web scripts that execute whenever an administrator views the form submissions page. The root cause was improper escaping of file upload URLs using esc_attr() instead of esc_url(), which was fixed in version 1.6.1 by improving validation and sanitization of uploaded file references. [1]

Useful 0 Not Useful 0

Impact Analysis

This vulnerability can impact you by allowing unauthenticated attackers to inject malicious scripts into the WordPress admin dashboard. When an administrator accesses the form submissions page, these scripts execute, potentially leading to session hijacking, credential theft, or other malicious actions within the admin context. This compromises the security and integrity of the WordPress site and its administrative functions. [1]

Useful 0 Not Useful 0

Detection Guidance

Detection of this vulnerability involves checking the version of the HTML Forms WordPress plugin installed. Since the vulnerability affects all versions up to and including 1.6.0, verifying if the plugin version is 1.6.0 or lower indicates exposure. There are no specific network commands provided to detect exploitation attempts, but you can inspect the WordPress admin dashboard for suspicious script injections in the form submissions page. To check the plugin version via command line, you can use WP-CLI with the command: `wp plugin get html-forms --field=version`. If the version is 1.6.0 or below, the site is vulnerable. [1]

Useful 0 Not Useful 0

Mitigation Strategies

The immediate mitigation step is to update the HTML Forms WordPress plugin to version 1.6.1 or later, where the vulnerability has been fixed by correcting the sanitization of file upload URLs. Additionally, ensure that only trusted users have access to the WordPress admin dashboard to reduce risk. Applying the update will prevent unauthenticated attackers from injecting arbitrary scripts via the file upload metadata. [1]

Useful 0 Not Useful 0