edward_plainview

Prevent password resets or changes to specific users or user roles. User-specific exceptions to the sweeping user roles can be set. The user’s password is then protected from modification:
<ul>
<li>In the user’s profile editor</li>
<li>Using the password reset link in the login window</li>
</ul>
The settings are available to either the super admin on the network, or normal admins on a single installation. If you wish to hide the settings completely, put the following in your wp-config.php:
<pre><code>define( 'PLAINVIEW_PROTECT_PASSWORDS_HIDE', true );
</code></pre>
Requires PHP 5.4.

Plainview Protect Passwords

I love that is works well with network sites so I don't have to replicate my settings across each of my sites. 

The only issue I ran into is that only network roles are added to the network settings. Maybe it's by design, but it would be awesome if it picked up the roles from the sites because that is where plugins like User Role Editor and WooCommerce have registered them. In order to protect these I would have to modify the settings for each of my network sites separately. Annoying but totally doable. 

Thanks for the quick and easy solution today!

Gets the job done

Selectively protect passwords from being reset or modified.

harrym

WordPress uses phpass to store passwords. Because WordPress has to work everywere, it uses the portable version of phpass, 
which uses MD5 to hash passwords. MD5 is not a very good hashing algorithm for passwords, because it’s relatively fast.
This plugin switches over to bcrypt, which is the algorithm recommended by phpass, and is a much better option for password 
storage because it is much slower to produce. This makes it much harder for an attacker who’s managed to access your hashed 
passwords to obtain plain text passwords by brute-forcing, or by trying passwords from a dictionary.
Note: this plugin requires PHP 5.3.0 or newer
Be aware that if you use this plugin and then move to a host that does not support bcrypt, you will need to reset any user 
account that you want to log in with.

wp-bcrypt

wp bcrypt switches WordPress's password hashes from MD5 to bcrypt, making it harder for them to be brute-forced if they are leaked.

Plainview Protect Passwords vs wp-bcrypt