CVE-2026-105882: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in ThemeGrill User Registration

The ThemeGrill User Registration plugin for WordPress versions prior to 5.3.0 contains a stored cross-site scripting vulnerability due to improper neutralization of input during web page generation. This flaw allows an attacker with low privileges to inject malicious scripts that are stored and later executed in the context of other users, requiring user interaction. The CVSS 3.1 vector indicates network attack vector, low attack complexity, low privileges required, user interaction required, and impacts confidentiality, integrity, and availability with low to partial severity.

Successful exploitation could allow an attacker to execute arbitrary scripts in the context of affected users, potentially leading to partial confidentiality, integrity, and availability impacts. This could result in unauthorized actions performed on behalf of users or disclosure of sensitive information within the affected application context.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, consider restricting user input fields and applying web application firewall rules to detect and block XSS payloads. Monitor vendor channels for updates and apply patches promptly once released.