LinkAce is a self-hosted archive to collect website links. Prior to version 2.5.7, the Bulk Link API endpoint (POST /api/v2/bulk/links) accepts URLs without any format validation, allowing an authenticated user to store a javascript: URI. The stored URI is later rendered verbatim as an href in Blade templates, and clicking it executes arbitrary JavaScript in the victim's browser — exfiltrating cookies and session tokens. Version 2.5.7 fixes the issue.