Client Invoicing by Sprout Invoices < 20.8.16 - Subscriber+ Private Note Overwrite via si_edit_private_note

The Sprout Invoices WordPress plugin before 20.8.16 does not perform a capability or ownership check before allowing a private note to be overwritten through one of its AJAX actions, allowing any authenticated user such as a subscriber to overwrite private notes on records belonging to other users.