CVE-2025-56515

Vulnerability

Overview CVE-2025-56515 is a stored cross-site scripting (XSS) vulnerability in the Fiora chat application version 1.0.0. The vulnerability arises from insufficient validation of SVG file content during user avatar uploads. The application fails to sanitize SVG elements, allowing attackers to embed malicious tags containing iframes and JavaScript event handlers (e.g., onmouseover) [1][2].

Exploitation

An authenticated user can upload a crafted SVG file as their avatar. When other users view the avatar (e.g., on profile pages or chat interfaces), the embedded JavaScript executes in their browser context. The attack requires no additional user interaction beyond viewing the affected profile, as the payload triggers automatically upon rendering [2].

Impact

Successful exploitation allows attackers to steal session cookies, perform unauthorized actions on behalf of the victim, and redirect users to malicious sites. The vulnerability bypasses existing XSS protections in the application, leading to full account compromise [1][2].

Mitigation

The vendor has confirmed the vulnerability, and a fix is pending. Users should upgrade to a patched version once available. In the interim, administrators can implement content security policies or manually validate SVG uploads [2][3].