Vulnerability Discussion

Support for NFS services is nonessential and, therefore, must be disabled. Enabling any service increases the attack surface for an intruder. By disabling unnecessary services, the attack surface is minimized.

Check

Verify the macOS system is configured to disable NFS service with the following commands:

isDisabled=$(/sbin/nfsd status | /usr/bin/awk '/nfsd service/ {print $NF}')
if [[ "$isDisabled" == "disabled" ]] && [[ -z $(/usr/bin/pgrep nfsd) ]]; then
echo "pass"
else
echo "fail"
fi

If the result is not "pass", this is a finding.

Fix

Configure the macOS system to disable NFS service with the following commands:

/bin/launchctl disable system/com.apple.nfsd
/bin/rm -rf /etc/exports

The system may need a restart for the update to take effect.