PR07-19: Cross-site Scripting (XSS) / HTML injection on Webbler CMS admin login page (2)

Date Found: 14th June 2007

Successfully tested on: Webbler CMS version 3.1.3. Earlier versions are possibly affected as well.

Severity: Medium/High

Note: The version number is usually included within 'meta' HTML tags and 'X-Powered-By'
HTTP response headers. i.e. -

<meta name="generator" content="webbler 3.1.3 - http://tincan.co.uk/webbler" />

X-Powered-By: webbler version 3.1.3

Description: Webbler CMS is vulnerable to XSS within the " /uploader/index.php" server-side script
and 'login' parameter.

No authentication is required to exploit this vulnerability.

Consequences: An attacker may be able to cause execution of malicious scripting code in the browser of a
user who clicks on a link to a site generated/managed by Webbler CMS. HTML tags can also
be injected.

This type of attack can result in non-persistent defacement of the target site, or the redirection
of confidential information to unauthorised third parties.

Proof of concept:

This vulnerability can only be exploited as a POST request, so the attacker must convince the victim to visit a third-party site which causes the victim's browser to submit the POST XSS request to the vulnerable site. This can be accomplished through a hidden '<form>' with a 'method="post"' attribute.

The following curl command can be used to test if a site is vulnerable:

curl -s "http://target-domain.com/uploader/?" -d "login=\"><script>alert(\"XSS\")</SCRIPT>&password=test&processlogin=Enter&forgotpassword="

Successfully tested on:

Server environment -

Webbler CMS 3.1.3
PHP 5.1.6
Apache web server (unknown version)

Client environment -

Microsoft Internet Explorer 7.0.5730.11

Author: Adrian Pastor [adrian.pastor [at] procheckup.com]. ProCheckUp thanks Tincan for fixing this vulnerability so promptly.

Fix: This issue has been fixed on version version 3.1.6.

References:

http://tincan.co.uk/webbler
http://tincan.co.uk/?lid=1975
http://www.procheckup.com/Vulner_2007.php

Legal:

Copyright 2007 Procheckup Ltd. All rights reserved.

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