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Exploit Title : SQl INJECTION AJAX Post Search --- wordpress plugin---
Author:Marcela Benetrix
home:www.girlinthemiddle.net
Date: 10/12/12
version: 1.1
software link: http://wordpress.org/extend/plugins/cardoza-ajax-search/
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AJAX Post Search wordpress plugin description
This plugin will allow your website visitors to search the posts of your site without page refresh.
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SQL (blind) injection description
The problem was located in :cardoza_ajax_search.php file, to be more specific  the_search_function() . I could see that the srch_txt field hadn't been sanitized.

POC:

/wp-admin/admin-ajax.php/?srch_txt='or 1=1-- &action=the_search_text

via ajax

it is possible to access the database and as a consequence  get user information such as usernames, passwords among other data

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Vendor Notification
10/12/2012 to: the developer. He replied immediately and fixed the problem.
posted in plugin track repository http://plugins.trac.wordpress.org/ticket/1588 
Because of it, a new version has been released