To restrict root logins on serial ports,
ensure lines of this form do not appear in '/etc/securetty':
ttyS0
ttyS1
[no/yes]
Preventing direct root login to serial port interfaces
helps ensure accountability for actions taken on the systems
using the root account.
oval:org.secpod.oval:def:31255
oval:org.secpod.oval:def:30532
SCAP Repo OVAL Definition
2015-11-13