Affected Systems
Discovered By
Vulnerability Details
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/
KoreLogic, Inc. is a founder-owned and operated company with a proven track record of providing security services to entities ranging from Fortune 500 to small and mid-sized companies. We are a highly skilled team of senior security consultants doing by-hand security assessments for the most important networks in the U.S. and around the world. We are also developers of various tools and resources aimed at helping the security community. https://www.korelogic.com/about-korelogic.html
Our public vulnerability disclosure policy is available at: https://korelogic.com/KoreLogic-Public-Vulnerability-Disclosure-Policy.v2.3.txt
Disclosure Timeline
KoreLogic submits vulnerability details to Barco.
Barco acknowledges receipt and the intention to investigate.
Barco notifies KoreLogic that this issue, along with several others reported by KoreLogic, will require more than the standard 45 business day remediation timeline. Barco requests to delay coordinated disclosure until 2020.12.11.
KoreLogic agrees to 2020.12.11 coordinated disclosure.
Barco informs KoreLogic of their intent to acquire CVE number for this vulnerability.
Barco shares CVE number with KoreLogic and announces their intention to release the updated firmware ahead of schedule, on 2020.11.11. Request that KoreLogic delay public disclosure until 2020.11.20.
Barco firmware release.
KoreLogic public disclosure.
Responsible Disclosure
KoreLogic follows responsible disclosure practices. All vulnerabilities are reported to affected vendors with appropriate time for remediation before public disclosure.