CVE-2026-63281 is a CWE-79 (Improper Neutralization of Input During Web Page Generation) vulnerability in the Regular Labs Advanced Module Manager extension for Joomla. Specifically, stored condition values can contain malicious HTML or JavaScript that executes in administrator summary views, resulting in a stored cross-site scripting (XSS) flaw. The vulnerability affects versions 1.0.0 through 11.0.1. The CVSS 3.1 base score is 4.8 (medium severity), reflecting network attack vector, low attack complexity, high privileges required, user interaction required, and impacts to confidentiality and integrity but not availability. There is no vendor advisory or patch available at this time, and no known exploits in the wild have been reported.

Successful exploitation could allow an attacker with high privileges and user interaction to execute arbitrary HTML or JavaScript in the context of administrator summaries. This may lead to limited confidentiality and integrity impacts, such as unauthorized disclosure or modification of information accessible to administrators. There is no impact on availability. The attack requires network access, high privileges, and user interaction.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, administrators should exercise caution when handling stored condition values in the Advanced Module Manager extension and consider restricting access to trusted users only. Monitor official regularlabs.com and Joomla advisories for updates.