Yes. If a user enters their password in Couchdrop incorrectly five (5) times within five (5) minutes, the user (not IP) will be locked out and blocked for 15 minutes. Users can unlock their own accounts by resetting their password.
This applies across all protocols (SFTP, SCP, FTP) and web portals.
Administrators can unlock the users. Administrators can also enable/disable this security function across the entire organization.