VU#125331: Adobe ColdFusion is vulnerable to privilege escalation due to weak ACLs

Overview

Adobe ColdFusion fails to properly set ACLs, which can allow an unprivileged Windows user to be able to run arbitrary code with SYSTEM privileges.

Description

The Adobe ColdFusion installer fails to set a secure access-control list (ACL) on the default installation directory, such as C:\ColdFusion2021\. By default, unprivileged users can create files in this directory structure, which creates a privilege-escalation vulnerability.

Impact

By placing a specially-crafted DLL file in the ColdFusion installation directory, an unprivileged user may be able to execute arbitrary code with SYSTEM privileges on a Windows system with the vulnerable ColdFusion software installed. See DLL Search Order Hijacking for more details.

Solution

Use the Server Auto-Lockdown Installer

By default, ColdFusion does not configure itself securely. In order to secure ColdFusion with respect to service privileges, ACLs, and other attributes, the ColdFusion Server Auto-Lockdown installer must be installed in addition to installing ColdFusion itself.

Mitigation steps will vary based on the version of ColdFusion being used:
ColdFusion 2016: Apply the changes outlined in the ColdFusion 2016 Lockdown Guide.
ColdFusion 2018: Run the ColdFusion 2018 Auto-Lockdown installer and ensure that it completes without error.
ColdFusion 2021: Run the ColdFusion 2021 Auto-Lockdown installer and ensure that it completes without error.

Acknowledgements

This vulnerability was reported by Will Dormann of the CERT/CC.

This document was written by Will Dormann.

Vendor Information

References

• https://helpx.adobe.com/coldfusion/user-guide.html/coldfusion/using/server-lockdown.ug.html
• https://wwwimages.adobe.com/content/dam/acom/en/products/coldfusion/pdfs/coldfusion-2016-lockdown-guide.pdf
• https://www.adobe.com/support/coldfusion/downloads.html#cf2018ldg
• https://www.adobe.com/support/coldfusion/downloads.html#cf2021ldg