Nextendweb Nextend Facebook Connect versions up to 3.1.19 contain a stored XSS vulnerability due to improper input neutralization during web page generation. This vulnerability allows an attacker with low privileges to inject malicious scripts that execute in the context of other users, potentially leading to partial confidentiality, integrity, and availability impacts. The CVSS 3.1 vector indicates network attack vector, low attack complexity, low privileges required, user interaction required, and scope change with low impacts on confidentiality, integrity, and availability.

Successful exploitation of this stored XSS vulnerability could allow an attacker to execute arbitrary scripts in the context of other users, potentially leading to partial disclosure of sensitive information, modification of data, or disruption of service. The impact is rated medium based on the CVSS score of 6.5. There are no reports of active exploitation in the wild.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, consider restricting user input that can be rendered in web pages and applying web application firewall (WAF) rules to detect and block XSS payloads. Monitor vendor channels for updates regarding patches or official mitigations.