File cracklib_dict.pwd not found when creating a new user or changing his password

Question

I have created new users and changed his/her password lots of times on Ubuntu, Xubuntu, Kubuntu, Lubuntu, Desktop, Server, Live... etc.

But, since a few weeks ago (I think it is due to the last system update), I am having problems at password management on my Ubuntu Server v14.04.1 LTS (sorry, my Ubuntu is in spanish, but I think it is easy to understand the issue):

luis@Balanceador:~$ sudo adduser prueba
[sudo] password for luis:
Anadiendo el usuario `prueba' ...
Anadiendo el nuevo grupo `prueba' (1002) ...
Anadiendo el nuevo usuario `prueba' (1002) con grupo `prueba' ...
Creando el directorio personal `/home/prueba' ...
Copiando los ficheros desde `/etc/skel' ...
Nueva contrasena:
/var/cache/cracklib/cracklib_dict.pwd: No existe el archivo o el directorio
BAD PASSWORD: The password fails the dictionary check - error cargando diccionario
Vuelva a escribir la nueva contrasena:
passwd: password updated successfully
Changing the user information for prueba

The main problem translates to: /var/cache/cracklib/cracklib_dict.pwd: No such file or directory.

Same behavior for changing passwords:

luis@Balanceador:~$ sudo passwd prueba
Nueva contrasena:
/var/cache/cracklib/cracklib_dict.pwd: No existe el archivo o el directorio
BAD PASSWORD: The password fails the dictionary check - error cargando diccionario
Vuelva a escribir la nueva contrasena:
passwd: password updated successfully

The password seems to be set OK, but I think it could be good to repair this bad password verification system.

How can I solve it?

Solution

Installing the package crack-lib solved it for me:

sudo apt-get install cracklib-runtime

I had it working fine too, but one day (after some update) it disappeared.