Barco wePresent Global Hardcoded Root SSH Password

Vulnerability Description

The Barco wePresent device has a hardcoded root password hash included in the firmware image. To our knowledge the password hash has not been cracked and published; it is possible this could occur at any time. This combined with KL-001-2020-004 (CVE-2020-28329), KL-001-2020-005 (CVE-2020-28330), and KL-001-2020-007 (CVE-2020-28331) could be used in a simple and automated exploit chain to go from unauthenticated remote attacker to root shell.

Technical Description

In looking at the unpacked firmware, a root hash was quickly identified in the /etc/shadow file on the device. It is the only account in the /etc/shadow. The device does not prompt the administrator to set a new root password, therefore this password is hardcoded and exists across all devices.

Mitigation and Remediation Recommendation

The vendor has released an updated firmware (2.5.3.12) which remediates the described vulnerability. Firmware and release notes are available at:

https://www.barco.com/en/support/software/R33050104

Credit

This vulnerability was discovered by Jim Becher (@jimbecher) of KoreLogic, Inc.

Proof of Concept

After unpacking the firmware:

$ ls -al etc/shadow
-rwxr-xr-x 1 user user 59 May 25 00:11 etc/shadow

$ cat etc/shadow
root:$1$reqE8o6b$[REDACTED]:12940:0:99999:7:::

The contents of this advisory are copyright(c) 2020 KoreLogic, Inc. and are licensed under a Creative Commons Attribution Share-Alike 4.0 (United States) License: http://creativecommons.org/licenses/by-sa/4.0/

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