amir tohidlo

Safe Headers Scanner helps WordPress administrators identify common issues that may cause header-related problems. 
The plugin scans installed themes and plugins for: 
* Unnecessary whitespace before <code><?php</code> tags 
* Extra whitespace after closing <code>?></code> tags 
* Direct output (e.g., <code>echo</code>, <code>print</code>) before headers are sent
Results are displayed in a clear report, so you can review and fix potential issues easily.

Safe Headers Scanner

Scan themes and plugins for potential header issues such as whitespace before/after PHP tags or direct output before headers.

atmosphear

Send an “HTTP/1.1 403 Forbidden” header on a failed login instead of “HTTP/1.1 200 OK”, which is the WordPress default header on failed login. This is a tremendously simple plugin that does only that and absolutely nothing else.
The purpose of this plugin is to provide a way to allow external tools like fail2ban to get a message of a failed login e.g. to prevent a brute-force attack on a firewall level.
For the public domain.
Uses PHP5.3 anonymous functions and will not work on earlier versions of PHP

HTTP/1.1 403 Forbidden header on a failed login

Send an "HTTP/1.1 403 Forbidden" header on a failed login instead of the default "HTTP/1.1 200 OK"

Safe Headers Scanner vs HTTP/1.1 403 Forbidden header on a failed login