The issue concerns the Piccolo Admin interface, which allows media file uploads, including SVG files by default. An attacker can upload a malicious SVG file, which, when loaded, can provide arbitrary access to the admin page. This access enables the attacker to perform various actions, such as gaining access to all data stored within the admin page, creating, modifying, or deleting table records. The vulnerability exploits the context of an authenticated admin session, allowing the attacker to make actions that would normally be restricted.