No MFA… And No Password!
I was recently on a CMMC assessment where the company had an Ubuntu machine. I asked them to log on and show me if multifactor authentication (MFA) was enabled.
They did. Everything looked good.
Then, I asked them to run an administrative command – one that should require superuser privileges like looking at log files. They typed:
sudo tail -20 /var/log/syslog
Guess what?
No password prompt. No MFA challenge. Straight to root access.
This is a common issue with Linux machines, especially when MFA is configured only for the initial login but not for privilege escalation.
Under CMMC, running administrative functions must require MFA, whether they’re run locally or remotely.
So do not assume that your Linux boxes are compliant. Make sure that the superuser access is protected with both password and MFA.