A stored cross-site scripting (XSS) vulnerability exists in the Altium Support Center AddComment endpoint due to missing server-side input sanitization. Although the client interface applies HTML escaping, the backend accepts and stores arbitrary HTML and JavaScript supplied via modified POST requests.

The injected content is rendered verbatim when support cases are viewed by other users, including support staff with elevated privileges, allowing execution of arbitrary JavaScript in the victim’s browser context.

A stored cross-site scripting (XSS) vulnerability exists in the user profile text fields of Altium 365. Insufficient server-side input sanitization allows authenticated users to inject arbitrary HTML and JavaScript payloads using whitespace-based attribute parsing bypass techniques. The injected payload is persisted and executed when other users view the affected profile page, potentially allowing session token theft, phishing attacks, or malicious redirects. Exploitation requires an authenticated account and user interaction to view the crafted profile.

A stored cross-site scripting (XSS) vulnerability exists in the Altium Forum due to missing server-side input sanitization in forum post content. An authenticated attacker can inject arbitrary JavaScript into forum posts, which is stored and executed when other users view the affected post. Successful exploitation allows the attacker’s payload to execute in the context of the victim’s authenticated Altium 365 session, enabling unauthorized access to workspace data, including design files and workspace settings. Exploitation requires user interaction to view a malicious forum post.