Saturday, February 12, 2022

Creston Web Interface - Credential Disclosure

# Exploit Title: Creston Web Interface - Credential Disclosure
# Exploit Author: RedTeam Pentesting GmbH

Advisory: Credential Disclosure in Web Interface of Crestron Device

When the administrative web interface of the Crestron HDMI switcher is
accessed unauthenticated, user credentials are disclosed which are valid
to authenticate to the web interface.


Product: Crestron HD-MD4X2-4K-E
Affected Versions:
Fixed Versions: -
Vulnerability Type: Information Disclosure
Security Risk: high
Vendor URL:
Vendor Status: decided not to fix
Advisory URL:
Advisory Status: published
CVE: CVE-2022-23178


"Crestron sets the gold standard for network security by leveraging the
most advanced technologies including 802.1x authentication, AES
encryption, Active Directory® credential management, JITC Certification,
SSH, secure CIP, PKI certificates, TLS, and HTTPS, among others, to
provide network security at the product level."

(from the vendor's homepage)

More Details

Upon visiting the device's web interface using a web browser, a login
form is displayed requiring to enter username and password to
authenticate. The analysis of sent HTTP traffic revealed that in
addition to the loading of the website, a few more HTTP requests are
automatically triggered. One of the associated responses contains a
username and a password which can be used to authenticate as the
affected user.

Proof of Concept

Requesting the URL "" via a web browser
results in multiple HTTP requests being sent. Among others, the
following URL is requested:


This request results in a response similar to the following:

HTTP/1.0 200 OK
Cache-Control: no-cache
Content-type: text/html

  "login_ur": 0,
  "front_val": [
  "uname": "admin",
  "upassword": "password"

The values for the keys "uname" and "upassword" could be used to
successfully authenticate to the web interface as the affected user.


Reachability over the network can be restricted for access to the web
interface, for example by using a firewall.


No fix known.

Security Risk

As user credentials are disclosed to visitors of the web interface they
can directly be used to authenticate to it. The access allows to modify
the device's input and output settings as well as to upload and install
new firmware. Due to ease of exploitation and gain of administrative
access this vulnerability poses a high risk.


2021-10-06 Vulnerability identified
2021-11-15 Customer approved disclosure to vendor
2021-12-08 Vendor notified
2021-12-15 Vendor notified again
2021-12-21 Vendor response received: "The device in question doesn't support
           Crestron's security practices. We recommend the HD-MD-4KZ alternative."
2021-12-22 Requested confirmation, that the vulnerability will not be addressed.
2021-12-28 Vendor confirms that the vulnerability will not be corrected.
2022-01-12 Advisory released

RedTeam Pentesting GmbH

RedTeam Pentesting offers individual penetration tests performed by a
team of specialised IT-security experts. Hereby, security weaknesses in
company networks or products are uncovered and can be fixed immediately.

As there are only few experts in this field, RedTeam Pentesting wants to
share its knowledge and enhance the public knowledge with research in
security-related areas. The results are made available as public
security advisories.

More information about RedTeam Pentesting can be found at:

Working at RedTeam Pentesting

RedTeam Pentesting is looking for penetration testers to join our team
in Aachen, Germany. If you are interested please visit:

RedTeam Pentesting GmbH                   Tel.: +49 241 510081-0
Dennewartstr. 25-27                       Fax : +49 241 510081-99
52068 Aachen          
Germany                         Registergericht: Aachen HRB 14004
Geschäftsführer:                       Patrick Hof, Jens Liebchen

Copyright © 2021 Vulnerability Database | Cyber Details™

thank you Templateism for the design - You should have written the code a little more complicated - Nothing Encrypted anymore