InvoicePlane 1.5.11 doesn't have any rate-limiting for password reset and the reset token is generated using a weak mechanism that is predictable.
https://seran.github.io/research/2021/03/16/weak-password-recovery-mechanism-in-invoiceplane.html
https://notnnor.github.io/research/2021/03/16/weak-password-recovery-mechanism-in-invoiceplane.html