A URL redirection vulnerability exists in UJCMS 9.6.3 due to improper validation of URLs in the upload and rendering of new block / carousel items. This vulnerability allows authenticated attackers to redirect unprivileged users to an arbitrary, attacker-controlled webpage. When an authenticated user clicks on the malicious block item, they are redirected to the arbitrary untrusted domains, where sensitive tokens, such as JSON Web Tokens, can be stolen via a crafted webpage.

A Stored Cross-Site Scripting (XSS) vulnerability exists in authenticated SVG file upload and viewing functionality in UJCMS 9.6.3. The vulnerability arises from insufficient sanitization of embedded attributes in uploaded SVG files. When a maliciously crafted SVG file is viewed by other backend users, it allows authenticated attackers to execute arbitrary JavaScript in the context of other backend users' browsers, potentially leading to the theft of sensitive tokens.