Indico is an event management system that uses Flask-Multipass, a multi-backend authentication system for Flask. Prior to 3.3.13, an authenticated user can misuse the legacy session export API to retrieve details for a restricted session without access to that session, as long as the containing event is accessible. The missing access check can disclose session metadata such as the title, description, and conveners. This issue is fixed in version 3.3.13.