Systems, devices, and methods for password protection of defined spaces in a memory device. The method includes receiving a data block from a host. The data block includes a user-defined current password, a user-defined new password, a password length of the current password, a password length of the new password, and a user-defined address range field including start and end addresses of a defined space in the memory device. The method further includes matching password lengths of the user-defined current password and a current password length of a current password for the defined space already stored in the memory device. The method also includes comparing the user-defined current password and the current password of the defined space. The method further includes replacing or resetting the current password of the defined space with the user-defined new password based on a result of the matching and a result of the comparing.