Vulnerability Note VU#870761

Dell Foundation Services (DFS) is a remote support component that is pre-installed on some Dell systems. DFS installs a trusted root certificate (eDellRoot) that includes the private key. This certificate was first installed in August 2015.

Dell systems that have been re-imaged or do not otherwise have DFS installed are not affected. ZMap has provided a page to test for this vulnerability: https://zmap.io/dell/

An attacker can generate certificates signed by the eDellRoot CA. Systems that trusts the eDellRoot CA will trust any certificate issued by the CA. An attacker can impersonate web sites and other services, sign software and email messages, and decrypt network traffic and other data. Common attack scenarios include impersonating a web site, performing a MiTM attack to decrypt HTTPS traffic, and installing malicious software.

Mark eDellRoot certificate as untrusted

Mark the eDellRoot certificate as untrusted. Using the Windows certificate manager (certmgr.msc), move the eDellRoot certificate from the Trusted Root Certificate Store to Untrusted Certificates. Marking the certificate as untrusted helps prevent reinstating trust if DFS is reinstalled or DFS reinstalls the certificate.

Remove eDellRoot certificate

Dell has issued guidance to remove the eDellRoot certificate in this blog post. It is important to both remove the eDellRoot certificate and the DFS component that re-installs the certificate. Dell has also provided a removal tool.

Administrators can Configure Trusted Roots and Disallowed Certificates for managed systems.

Update Certified Trust List

Microsoft Security Advisory 3119884 documents updates to the Certified Trust List (CTL) to mark the eDellRoot certificate as untrusted. Most Windows systems will automatically receive the updated CTL.