The WP Dropzone plugin for WordPress suffers from a stored XSS vulnerability due to insufficient input sanitization and output escaping of the 'callback' shortcode attribute. This attribute is processed using the JavaScript `new Function()` constructor, allowing authenticated users with Contributor or higher privileges to inject arbitrary scripts. These scripts execute in the context of any user viewing the compromised page, potentially leading to session hijacking or other script-based attacks. The vulnerability affects all versions up to and including 1.1.1. No known exploits are reported in the wild, and no patch links or vendor advisories have been provided.

An attacker with Contributor-level or higher access can inject persistent malicious JavaScript code into pages via the vulnerable 'callback' attribute. This code executes in the browsers of users who visit the infected pages, potentially leading to information disclosure or session compromise. The vulnerability does not impact availability and requires authenticated access with low attack complexity. The scope is changed as the vulnerability affects other users beyond the attacker. No known active exploitation has been reported.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is released, restrict Contributor-level access to trusted users only and consider disabling or removing the WP Dropzone plugin if possible. Monitor for updates from the plugin vendor or WordPress security channels for a patch or official mitigation instructions.