Vladimir Kolesnikov

Like any other software WordPress does have bugs and security vulnerabilities. They get fixed when the developers become aware of them. 
However, sometimes several WordPress releases are vulnerable. The problem is that the developers do not backport security updates to older WordPress releases. 
As a result, those who do not want to upgrade their WordPress installations (for example, because newer WP releases tend to consume more system resources and 
upgrade may result in having to use more expensive hosting) remain vulnerable.
ICS Security Fixes is the plugin for those who do not upgrade their WordPress: the plugin tries to fix known WordPress vulnerabilities 
at that remaining compatible with as many old WordPress releases as possible. 
And though it cannot fix all known vulnerabilities, it makes older WordPress installations more secure.
<h3>Warning</h3>
This plugins requires that PHP 5 be installed. PHP 4 is not supported.

ICS Security Fixes

The plugin tries to fix known WordPress vulnerabilities for older WordPress versions. Warning: For PHP 5 only.

dano1066

The thread of hackers is becoming a bigger concern every day. As tools get smarter and faster, it has become much easier for websites to get hacked. Often the hack can be performed by an automated tool if it discovers that your site has some pretty simple vulnerabilities. Quite often people don’t know of these security back doors or may have overlooked something that seems insignificant, but can actually be a back door into your system.
This plugin will perform a scan of your WordPress site along with the settings and configurations available to the underlying code to check for any vulnerabilities in your webserver. If an issue is detected the plugin will advise you the best course of action to take in order to resolve the issue.

System Vulnerability Scanner

Can be difficult to remember everything, even when you know what needs to be done. Handy to have this explain it all.

Valuable for setting up new servers

This plugin will scan your Wordpress site in order to check if there are settings and configurations with your web server, PHP or with wordpress that  …

ICS Security Fixes vs System Vulnerability Scanner