Incorrect authorisation in Adiss’s Biloop

Summary

An authenticated user could manipulate a company ID parameter in a POST request to the backend to gain unauthorised access to other companies hosted within the same subdomain environment. The application does not adequately verify whether the requested company ID belongs to the authenticated user’s session, resulting in a cross-tenant authorisation bypass. If this vulnerability is successfully exploited, it allows unauthorised access to sensitive customer information, including billing data, and may enable the unauthorised modification of third-party data.