Capgo Authentication Bypass via Direct PostgREST org_users Table Write

Capgo (capgo.app) exposes the legacy membership table public.org_users directly through Supabase PostgREST. The table's row-level security policies "Allow org admin to insert" and "Allow org admin to update" only verify that the caller has admin rights in the target organization (public.check_min_rights('admin', ...)); they do not require a pending invitation in tmp_users, acceptance of an invite token via /private/accept_invitation, any action by the target user, or the membership/role-consistency and anti-escalation checks enforced by the RBAC role-binding path. As a result, an authenticated user who is an admin of an organization can INSERT or UPDATE org_users rows directly to add any existing public.users account as an active member of that organization with user_right="admin", bypassing the invitation and role-assignment workflow entirely. In testing, an account with no prior access to the organization or its apps could, after such a direct insert, read the organization and app and pass check_min_rights. All versions are affected and no patch was available at the time of publication.

The application performs an authorisation check, but it does not correctly enforce the required permission boundary.

An attacker operating through a network path may attempt exploitation with low privileges. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.