ICS SCADA & Industrial Protocol Security 3

Question 1

What is 'defense in depth' as applied to ICS cybersecurity?

Accepted Answer

Applying multiple overlapping layers of security controls so that failure of one layer does not result in total compromise

Answer

Deploying a single, extremely robust security control at the network perimeter

Answer

Focusing all security resources exclusively on the most critical PLCs

Answer

Requiring antivirus software on all ICS endpoints regardless of impact on operations

Question 2

Which NIST publication serves as the primary guide for securing Industrial Control Systems?

Accepted Answer

NIST SP 800-82

Answer

NIST SP 800-53

Answer

NIST SP 800-171

Answer

NIST SP 800-61

Question 3

What is a 'data historian' in an ICS environment and why is it a security concern?

Accepted Answer

A time-series database server that stores process data and often bridges IT and OT zones, creating a potential attack pathway

Answer

A log management system for recording network security events in the OT zone

Answer

A backup system that archives PLC ladder logic programs

Answer

A firewall that records all inter-zone communications for forensic analysis

Question 4

What is the purpose of a Demilitarized Zone (DMZ) placed between an IT network and an OT network?

Accepted Answer

To create an intermediate buffer zone that controls and mediates data exchange between the IT and OT environments

Answer

To eliminate the need for firewalls between corporate and industrial networks

Answer

To allow unrestricted bidirectional data flow between both networks for operational efficiency

Answer

To host internet-facing SCADA dashboards accessible by external stakeholders

Question 5

A false data injection attack against a SCADA system is best described as:

Accepted Answer

Manipulating sensor or process data transmitted to the SCADA system so operators receive false readings and make incorrect control decisions

Answer

Flooding the SCADA master station with traffic to cause a denial of service

Answer

Injecting malicious code into PLC firmware during a software update

Answer

Exploiting SQL vulnerabilities in the SCADA historian database

Question 6

Which international standard specifically addresses cybersecurity for Industrial Automation and Control Systems (IACS)?

Accepted Answer

IEC 62443

Answer

ISO 9001

Answer

NIST CSF

Answer

PCI DSS

Question 7

In IEC 62443, the concept of 'security zones and conduits' refers to:

Accepted Answer

Grouping ICS assets with similar security requirements into zones and defining tightly controlled communication pathways (conduits) between those zones

Answer

Physical fencing and locked enclosures for ICS hardware

Answer

Encrypted tunnels between remote SCADA sites and the control center

Answer

Access control lists applied to individual PLCs and RTUs