jojaba

This plugin makes it possible to restrict the access of posts contained in categories by setting a password and giving the impacted categories. The content and the excerpt of these posts are replaced by a password form that the user can fill out to get access. The WordPress generated feeds are modified (the description is replaced by a sentence that you can define).
Here’s the list of the settings (see screenshots for further infos):
<ul>
<li>Choose between session or cookie authentication</li>
<li>Set the password</li>
<li>Check the categories that has to be protected</li>
<li>Check the users granted to access the categories without password</li>
<li>Tell if the excerpt should be displayed or not in resources listing</li>
<li>Display a custom excerpt before password field</li>
<li>Set the info message that display before the password form</li>
<li>Set the placeholder in password field</li>
<li>Set the error message when typing the wrong password</li>
<li>Set the valdation button text</li>
<li>Set the text replacing the feed item description of protected posts</li>
<li>You can style the form using the available classes</li>
</ul>
Availabe languages : English (1.5), French (1.5), Simplified Chinese (thanks to Changmeng Hu, 1.4), German (1.4).
This plugin uses php Sessions (more secure) or a Cookie (less secure) to keep in mind the authenticated users. The password is crypted before it is stored. The regular feed content is filtered to avoid content display of restricted categories posts.

Access Category Password

protection type COOKIE is insecure.

If User set browser COOKIE, he can access protected posts.
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protection type がCOOKIEの場合は安全面に問題があります。

ある名称のCOOKIEをブラウザに埋め込めば保護された投稿にアクセス可能で、それはとても簡単にできます。

The protection type "COOKIE" is deprecated as insecure.

Protects posts in categories by setting a unique Password for all restricted categories.

NUCUTA

‘Nucuta Password Protect’ is a security plugin which password protects wordpress websites. Requires PHP 5.6.30 or Above.
The plugin uses a custom password, and therefore it’s completely independant from default wordpress password uses to access to the admin area of the site. Users can be restricted to access the site either based on their user group or altogether.
The available user groups are “editor”, “author”, “contributor”, “subscriber”. if a particular group is excluded from protecting from the custom password, users belong to that group won’t be asked the password. Clicking on the log off button logs off from the entire website, meaning the user has to enter the password to access the site again. By default, all users (both guests and registered logged in users) are required to enter the password before accessing the site, but by configuring, logged in users can be excluded. The plugins blocks not only visitors, but also bots, spiders, and all kind of crawlers.
Custom message can be set for both logged in/non-logged in users, A separate login page is provided to login purpose. Password is salted before storing in the database, and therefore security is top notch. The full documentation, and how to use guide can be found at this location. <a href="https://nucuta.com/how-to-password-protect-wordpress-site/" rel="nofollow ugc">Documentation, Help and Tutorial</a>

Nucuta Password Protect

works even on php 7

Secure your wordpress site with a password. Useful for private blogs.

Access Category Password vs Nucuta Password Protect