Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in Forcepoint Web Security (Transaction Viewer) allows Stored XSS. The Forcepoint Web Security portal allows administrators to generate detailed reports on user requests made through the Web proxy. It has been determined that the "user agent" field in the Transaction Viewer is vulnerable to a persistent Cross-Site Scripting (XSS) vulnerability, which can be exploited by any user who can route traffic through the Forcepoint Web proxy. This vulnerability enables unauthorized attackers to execute JavaScript within the browser context of a Forcepoint administrator, thereby allowing them to perform actions on the administrator's behalf. Such a breach could lead to unauthorized access or modifications, posing a significant security risk. This issue affects Web Security: before 8.5.6.