laceous

Due to lack of interest (both my own and based on the number of downloads) this plugin will not be updated for WP 3.0
WordPress’ auth cookies include a built-in expiration date (either 2 or 14 days depending on if the ‘Remember Me’ option is checked). Even if you remove the client-side cookie (by manually logging out or just closing your browser if ‘Remember Me’ wasn’t checked when logging in) the data that was stored within the cookie is still valid until the expiration date is reached.
This could be an issue if someone managed to “steal” your cookie(s). They would still be able to access your website for some time into the future.
This plugin will immediately invalidate your auth cookies when you manually log out. This, of course, also means that you have to manually click ‘Log out’ for this plugin to work properly (you can’t just close your browser to remove any cookies that expire at the end of the session). This won’t prevent session hijacking, but should limit the amount of time that an attacker can access your website.

Invalidate Logged Out Cookies

This plugin will immediately invalidate your auth cookies when you manually log out.

webvitaly

<ul>
<li><a href="https://1.envato.market/KdRNz" title="Advanced iFrame Pro" rel="nofollow ugc">Advanced iFrame Pro</a></li>
<li><a href="http://web-profile.net/wordpress/plugins/login-logout/" title="Plugin page" rel="nofollow ugc">Login-Logout</a></li>
<li><a href="http://web-profile.net/donate/" title="Support the development" rel="nofollow ugc">Donate</a></li>
<li><a href="https://github.com/webvitalii/login-logout" title="Fork" rel="nofollow ugc">GitHub</a></li>
</ul>
“Login-Logout” plugin adds widget with login or logout link. Also can be shown register or site-admin link. It is the replacement of the default Meta widget.
<h4>If user is not logged in there are such links:</h4>
<ul>
<li>login (after login action user will return to previous page);</li>
<li>register (if user can register) (if checkbox is active);</li>
</ul>
<h4>If user is logged in there are such links:</h4>
<ul>
<li>welcome text with link to user profile (if checkbox is active);</li>
<li>logout (after logout action user will return to previous page);</li>
<li>site admin (if checkbox is active);</li>
</ul>

Login-Logout

Widget with login, logout, admin and register links. Replacement of the default Meta widget.

Invalidate Logged Out Cookies vs Login-Logout