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Cyber Security for the Smart Grid:

A R&D Perspective

Manimaran Govindarasu

Dept. of Electrical and Computer Engineering

Iowa State University

Email:

[email protected]

http://powercyber.ece.iastate.edu

NATO Advanced Institute on Energy Security

Antalya, Turkey, October 4-11, 2015

(2)

Outline

Basics of cyber security concepts

Cyber Security of WAMPAC - overview

Cyber Risk Assessment - overview

Cyber Security Testbeds - overview

Cyber Security Standards & Best practices

AMI Security & Privacy

(3)

Smart Grid: A Cyber-Physical System

(4)

Smart Grid: A Cyber-Physical System

(5)
(6)
(7)

Cyber Threats to Critical Infrastructures

Cyber-Based Attacks

Protocol

Attacks

Intrusions

Worms /

Spyware/

Malware

Routing

Attacks

Denial of

Service (DoS)

[General Accounting Office, CIP Reports, 2004 to 2010]; [NSA “Perfect Citizen”, 2010]:

Recognizes that critical infrastructures are vulnerable to cyber attacks from numerous sources, including hostile governments, terrorist groups, disgruntled employees, and other malicious intruders.

Insider

Threats

(8)

Power Grid Cyber Security Roadblocks

Legacy systems

Geographically disperse

Insecure remote connections

Long system deployments

Limited physical protections

Adoption of standardized technologies with known

vulnerabilities

Connectivity of control systems to other networks

No “fail-closed” security mechanisms

(9)

Securing system is difficult …

Open and interoperable protocols

Security vs. performance tradeoff

Security vs. usability tradeoff

Security is expensive

Attackers enjoy breaking into a system

Security had been not a design criteria

(10)

1.3 Information & Network Security

concepts

(11)

Security Properties

Confidentiality:

Message content should be accessed by authorized users only

Achieved by using

encryption

Integrity:

Making sure that message was not altered

(in transit, or later) without

detection

Achieved by using hashing

Availability:

services must be accessible and available

to authorized users

Authentication:

Sender, receiver want to confirm identity of each other

Achieved by using digital signatures

Non-Repudiation:

The actual sender can not claim that he did not send the message

(12)
(13)
(14)
(15)

Security Properties

Traditional IT Systems

Industrial Control Systems

Confidentiality

Availability/Integrity

Integrity

Integrity/Availability

Availability

Confidentiality

Power Grid

Applications

Information &

Infrastructure Security

Application Security

AMI

I, AT, C

I, N

DMS

I, A, AT

I, AT

EMS

I, A, AT

I, AT

WAMPAC

I, A, AT, C

I, A

Power Markets

I, A, AT, C

I, N

Priorities

Power Grid Applications – Sample Cyber Security Requirements

(16)

Network Security – Firewalls

Source: Guidelines on Firewalls and Firewall Policy, NIST Special Publication 800-41, September 2009.

Firewalls control flows of network traffic between networks or hosts based on security

policies.

Create firewall policies that specifies

how

firewalls should handle inbound and outbound

network traffic.

Identify all requirements that should be

considered when determining which firewall to

implement.

Create rule sets that implement the organization’s

firewall policy while supporting firewall

performance.

Manage firewall architecture, policies, software,

and other components throughout the life of the

firewall solutions.

(17)

Network Security – Firewalls

Source: Guidelines on Firewalls and Firewall Policy, NIST Special Publication 800-41, September 2009.

Packet Filtering

Stateful Inspection

Application Firewalls

Application-Proxy Gateways

Dedicated Proxy Servers

Virtual Private Networking

Network Access Control

Unified Threat Management

Web Application Firewalls

Firewalls for Virtual Infrastructures

Firewall Technologies

Policies based on IP Addresses and Protocols

IP addresses and IP characteristics

IPv6

TCP and UDP

ICMP

IPsec protocols

Policies based on Applications

Policies based on User Identity

Policies based on Network Activity

(18)

Network Security – IDS

Source: Guide to Intrusion Detection and Prevention Systems (IDPS), NIST Special Publication 800-94, February 2007.

Intrusion detection

is the process of monitoring the events occurring in a computer

system or network and analyzing them for signs of possible incidents.

Intrusion prevention

is the process for performing intrusion detection and attempting

to stop detected possible incidents.

Types of Intrusion Detection and Prevention Systems

Network-Based

– monitors network traffic for suspicious

activity

Wireless

– monitors wireless network traffic for suspicious

activity

Network Behavior Analysis

– examines traffic to identify

threats that generate unusual traffic flows, e.g. DDoS attacks,

malware, policy violations

Host-Based

– monitors characteristic of a single host and

events occurring for suspicious activity

Signature-Based Detection

Anomaly-Based Detection

Stateful Protocol Analysis

(19)

Network Security – IDS

Source: Guide to Intrusion Detection and Prevention Systems (IDPS), NIST Special Publication 800-94, February 2007.

(20)

Network Security – WLAN Security

WLAN’s are extensions to wired LAN’s based on IEEE 802.11 standard.

Fundamental architecture of WLAN consists of Access Points (AP), client devices, and

Distribution Systems (DS) that connect to wired LAN’s.

Source: Guidelines for Securing Wireless Local Area Networks (WLANs), NIST Special Publication 800-153, February 2012.

Steps to minimize risk:

1.

Password Policies & management

1.

Encrypt data using standards like WPA2

1.

Restrict access using security controls

1.

Mac address filtering

2.

Disable appropriate network

interfaces, bridging traffic

1.

Configure host-based network security

tools like firewalls, IDS

(21)

Smart Security = Info + Infra + System

Information Security

Infrastructure Security

Control Systems Security

N

E

E

D

S

Information Protection

Message

Confidentiality

Message Integrity

Message Authenticity

Infrastructure protection

Routers

DNS servers

Links

Internet protocols

Service availability

Generation control apps.

Transmission control apps.

Distribution control apps.

Real-Time Energy Markets

M

E

A

N

S

Encryption/Decryption

Digital signature

Message Auth.Codes

Public Key Infrastructure

Traffic Monitoring

Statistical analysis

Authentication Protocols

Secure Protocols

Secure Servers

Attack-Resilient Control Algos

Model-based Algorithms

- Anomaly detection

- Intrusion Tolerance

- Bad data elimination

Risk modeling and mitigation

(22)

Summary

SCADA and automation concepts

Cyber Threat landscape, Coordinated attacks on

WAMPAC, and consequences

Information security concepts – Symmetric and

asymmetric key cryptography, digital signatures

Network security concepts – Firewalls, IDS, WLAN

(23)
(24)

Control Systems Attack Model

Yu-Hu. Huang, Alvaro A. Cardenas, S. Amin, S-Z. Lin, H-Y. Tsai, and S. Sastry, “Understanding the Physical and Economic Consequences of Attacks on Control Systems,” International Journal of Critical Infrastructure Protection, 2(3):72-83, October 2009.

Data integrity

Replay

Denial of service

De-synchronization

and timing-based

Types of Attacks

Generic Control System Model

Cyber

System

Physical

System

Control Signal Sensing Signal Integrity Attack DoS Attack Signal
(25)

Cyber attack classification

Denial of Service attacks

• e.g. flood communication network and affect command

information flow

Timing attacks

Attacks on measurements or controls

• e.g., block instead of trip, VAR increase instead of

decrease.

Data integrity

attacks

Attacks coordinated in space, and/or time

• e.g.

attack on SPS of major transmission line followed by

attack on sub-transmission and distribution feeders

(26)
(27)

Beyond IT Security – Why?

• Limited encryption

capabilities

• Poor patch

management

• Software bugs

• Security not design

criteria

• Replay attacks

• Denial Of Service

attacks

• Timing attacks

• E.g., Heartbleed bug

• Secure system today

Vulnerable system

tomorrow

• Information and

infrastructure security

secure the entry points

• Application security

identifies anomalies in

data when IT and

infrastructure security fails

Legacy Infrastructure

Encrypted comm. can

also be tampered

Evolving Vulnerability

and Threat landscape

(28)

Smart Security = Info + Infra + System

Information Security

Infrastructure Security

Control Systems Security

N

E

E

D

S

Information Protection

Message

Confidentiality

Message Integrity

Message Authenticity

Infrastructure protection

Routers

DNS servers

Links

Internet protocols

Service availability

Generation control apps.

Transmission control apps.

Distribution control apps.

Real-Time Energy Markets

M

E

A

N

S

Encryption/Decryption

Digital signature

Message Auth.Codes

Public Key Infrastructure

Traffic Monitoring

Statistical analysis

Authentication Protocols

Secure Protocols

Secure Servers

Attack-Resilient Control Algos

Model-based Algorithms

- Anomaly detection

- Intrusion Tolerance

- Bad data elimination

Risk modeling and mitigation

(29)

WAMPAC Applications

Monitoring

Control

Protection

State Estimation

(SE)

Automatic Generation

Control (AGC)

Remedial Action

Schemes (RAS)

Situational Awareness

Generation/Load balance

Prevent system instability

Wide-Area Measurements

(SCADA and PMU network)

(30)

Cyber physical security of WAMPAC

1

• Vulnerability

Assessment

2

• Attack classification

3

• Attack Impact metrics

4

• Impact analysis

5

• Mitigation development

6

• Experimental validation

Attack model

Attack vectors

Impact

Analysis

Attack Mitigation

Research areas

R&D Methodology

Attack/Defense

Evaluation

(31)

Synchrophasors

Phasors –

Magnitude

Angle

Synchrophasors –

Common measurement

time-stamp using GPS

(32)

SCADA vs. PMU data

SCADA data:

Voltage & Current

Magnitudes

Data rate

Every 2-4 seconds (per sample)

PMU data:

Voltage & Current

Magnitudes

Phase angles

Frequency

Rate of change of frequency

Time synchronized (using GPS Satellite)

Data rate

30 -120 samples per second

SCADA DATA

(33)

PMU deployment worldwide (2009)

Source

: Chakrabarti, Kyriakides, Bi, Cai and Terzija, “Measurements Get Together,” IEEE Power & Energy

magazine, Jan/Feb 2009.

(34)
(35)

Risk Assessment and Risk

Management Process

(36)

Risk Assessment & Mitigation

(37)

Risk Assessment

Hierarchical Risk Modeling

System

Vulnerability

Scenario Vulnerability

Access Point Vulnerability

Real-Time Monitoring

Threat & Vulnerability Analysis

Impact Analysis

Defense measures

high risk

low risk

Risk = Threat x Vulnerability x Impacts

System Vulnerability Scenario Vulnerability Access point Vulnerability

(38)

Risk Management Process

(39)

Hierarchical Risk Management Model

(40)

Qualitative Risk Analysis Matrix

Combines the

probability

and

consequence

of a risk to

identify a

risk rating

for each individual risk.

Risk ratings

Represents a judgment as to the relative risk to the project

Categorizes each risk as

Low

Moderate

(41)

Qualitative Risk Analysis Matrix

(42)

Risk Assessment - Quantitative

Mitigation of

Coordinated Attacks

Offline:

Risk Modeling and Mitigation

Online:

Alert Correlation and Mitigation

Cyber System Definition

(Topology, Security)

Power System Definition

(Control, Protection)

Cyber System Modeling

(Petri Nets)

Power System Modeling

(DIgSILENT, PSSE)

Attack Probability Impact

Offline Mitigation

Attack Template

if risk > threshold

E.g. - Modify settings, Add security

E.g. - Increase transmission capacity







risk

(43)

Qualitative vs. Quantitative

Property

Qualitative

Quantitative

To be viable …

Relies on Expert Knowledge

Data sets, probabilities

Benefit …

Coarse-grain analysis

Fine-grain analysis

Analyzability …

Subjective?

Verifiable if assumptions hold

Security investment

High-level

Detailed analysis

Who uses

Industry

Academic

Both are complimentary !

Threat modeling is not well understood

- more of an art than science

Vulnerability assessment is subjective –

assumptions on cyber system

(44)

Mission Oriented Risk and Design Analysis

(MORDA)

(45)

Attack Trees

Source: NERC Cyber Attack Task Force report, May 2012 (www.nerc.com)

(46)

NERC CATF Risk Mitigation Framework

(47)

Cyber-Physical Security Testbeds

Adam Hahn, Aditya Ashok, Siddharth Sridhar, Manimaran Govindarasu,

Cyber-Physical Security Testbeds:

(48)

Need for Testbeds

1

• Vulnerability Analysis

2

• Impact Analysis

3

• Mitigation Research

4

• Cyber-Physical Metrics

5

• Data and Model Development

6

• Security Validation

7

• Interoperability

8

• Cyber Forensics

9

• Operator Training

(49)

CPS Testbed – A Layered View

Information/Control

Layer

Physical Layer

Communication Layer

attacks

Cyber

EMS, SAS, RTUs, IEDs

Routing infrastructure,

Network protocols,

Routers, Firewalls

Power System

Simulators (RTDS,

Power factory)

Defenses

Aditya Ashok, Adam Hahn, and Manimaran Govindarasu, “A cyber-physical security testbed for smart grid: system architecture and studies”, Proceedings of the Cyber Security and Information Intelligence Research (CSIIRW '11).

(50)

Cyber Security Testbeds

National SCADA test bed (NSTB) @ Idaho National Lab

Virtual Control System Environment @ Sandia National Lab

SCADA Security Testbed @ Pacific Northwest National Lab

PowerCyber Security Testbed @ Iowa State University

SCADA Security Testbed @ Washington State University, Pullman

Virtual Power System test bed (VPST) @ University of Illinois, Urbana

Critical Infrastructure Security Testbed @ Mississippi State University

(51)

Iowa State’s PowerCyber Testbed

Adam Hahn, Aditya Ashok, Siddharth Sridhar, Manimaran Govindarasu, Cyber-Physical Security Testbeds: Architecture, Application, and Evaluation for Smart Grid,

(52)

Visualization

USC/ISI DETER Testbed

ISU PowerCyber Testbed

(53)

Cyber Security Compliance &

Best practices

(54)

Cyber and Control Systems Security Standards

for Electric Power Systems

IEEE –

Institute of Electrical and Electronics Engineers

IEC

– International Electro-technical Commission

NERC

– North American Electric Reliability Council

CIGRE

– International Council on Large Energy Systems

FERC

– Federal Energy Regulatory Commission

PSRC

– Power Systems Reliability Committee

Organizations for Cyber Security Standards

Cyber Security Standards for Electric Power Systems

Protocol

Scope

IEEE 1402

Electric Power Substation Physical and Electronic Security

IEC 62351

Data and Communication Security

NERC 1300

Cyber Security Standards (CIP Standards) [www.nerc.com]

FERC SSEMP

Security Standards for Electric Market Participants

(55)

NISTIR 7628 – Guidelines for Smart Grid Cybersecurity

Vol. 1

Security Strategy, Architecture and High-Level Requirements

Applicability of CIA in the smart grid environment

Access control, Cryptography and key management

Risk management and assessment

Vol. 2

Privacy and the Smart Grid

New privacy concerns and classification of privacy

Laws and regulations with respect to privacy

Vol. 3

Supportive Analysis and References

Vulnerability definition and classification

Bottom-up Security Analysis

Security requirements –

Device security

Cryptography and key management

Network security

(56)

NIST – Smart Grid Interoperability Panel

NIST – Smart

Grid Scope

Standards Development

Research

Energy management and Metering

Smart-grid Architecture and Operations

Wide-Area Monitoring and control

Communication protocols and cybersecurity

Electric vehicles and storage

Interoperability standards

Cybersecurity standards

[

NISTIR 7628

– Guidelines for

Smart Grid Cyber Security]

(57)

NISTIR 7628 – Smart Grid Cyber Security Strategy

1. Use case analysis

Top-down analysis

(inter-component/domain)

Bottom-up analysis

(vulnerability classes)

2. Risk Assessment

Identify assets

Vulnerabilities

Threats

Impacts

3. High-level security

requirements

Privacy

Assessment

4a. Security

Architecture

4b. Smart Grid

Standards Assessment

Existing standards (IEEE,

CIP, etc.)

5. Conformity

Assessment

(58)

NERC – Critical Infrastructure Protection (CIP)

Objective:

Physical, cyber and operational security for bulk power system

Vulnerability and risk assessment

Threat response

Physical security

IT/Cyber security

Protecting sensitive data

Communications

NERC CIP

Scope

Support operation and protection

Deterrence, prevention, detection

and correction

Production, storage, transmission and disposal Facility and field

equipment Cyber and physical

countermeasures

Identify vulnerabilities and countermeasures

(59)

NERC – CIP Standards (Version 5)

CIP - 002

BES Cyber System Categorization

Security Management Controls

Personnel & Training

Electronic Security Perimeter(s)

Physical Security of BES Cyber

Systems

Systems Security Management

Incident Reporting and Response

Planning

Recovery Plans for BES Cyber

Systems

CIP - 004

CIP - 006

CIP - 008

CIP - 003

CIP - 005

CIP - 007

CIP - 009

Configuration Change Management

and Vulnerability Assessments

Information Protection

CIP - 010

(60)

Cyber security Best Practices

Defense in Depth

approach

Protect network boundaries

Protect computing environment

Firewalls

Limit inbound and outbound connections

Authorize appropriate outbound

connections

Filter malicious traffic

Intrusion Detection Systems

Analyze network traffic in near real-time

Based on signatures, anomaly based

Regular OS patching and updating

OS Hardening

Periodic Anti-virus updates

Use of Host based Firewalls

Routine Vulnerability Scanning

Use of Proxy servers and Web

content filters

Email attachment filtering

Monitoring logs

Authorize devices on LAN

(61)

ICS-CERT best practices

Minimize network exposure for all control system devices.

Firewall and isolate control network

Secure remote access using VPN’s

Account lockout policies

Password management policies

Access control management policies

Patch management policies

(62)

Vulnerability Lifecycle

Creation

Discovery

Notification

Mitigation

Released

Mitigation

Applied

Vendor mistake in

design/development

process

(Vendor/Coordinator/Rese

archer) disclose the

vulnerability to utilities

and/or general public

Vendor provides patch

and/or configuration

strategy to mitigate the

issue

Vulnerability discovered by

(Vendor/ Utility/Security

Researcher/Attacker)

Utilities/System integrators

work on testing, deploying

patch

(63)

Vulnerability Assessment

Inspect weaknesses in industry standards, software

platforms, network protocols and configurations

Common activities include

Vulnerability Scanning

Cryptography Analysis

Software fuzz testing

Common tools

Nmap – a security scanner to discover hosts and services

on a network

Wireshark – a network packet sniffer & analyzer tool

Nessus – a comprehensive vulnerability scanning program

Footprinting

Scanning

Enumerating

Exploit!

(64)

Multiple layers & Multiple vendors

Heterogeneous environment with both

industry-specific and traditional IT software

Must be able to flexibly manage vulnerabilities

discovered in both domains

Application

Network

Infrastructure

Operating

System

Web Database Email SCADA EMS WAMS SPS

Ethernet TCP/IP SSL NTP DNP3 IEC-TC57 Modbus

Microsoft Unix Linux IOS VXworks Embedded

(65)

Vulnerability Disclosure

ICS-CERT Advisory

An ICS-CERT Advisory is intended to provide awareness or

solicit feedback from critical infrastructure owners and

operators concerning ongoing cyber events or activity with

the potential to impact critical infrastructure computing

networks. (

http://ics-cert.us-cert.gov

)

NERC ES-ISAC

“Facilitates sharing of information pertaining to physical and

cyber threats, vulnerabilities, incidents, potential protective

measures, and practices”. (

http://www.nerc.com

)

(66)

ICS CERT Advisory

A typical ICS-CERT Advisory contains:

Affected products

Impact

Background

Vulnerability Characterization

Vulnerability Overview

Vulnerability Details

Exploitability

Existence of Exploit

Difficulty

Mitigation

(67)
(68)

Need for Advanced Metering Infrastructure

(AMI)

System Operation

Benefits

Reduction in peak loads Improved Monitoring and control Improved efficiency and reliability Cost reduction

Customer Service

Benefits

Billing accuracy and flexible billing cycle

Time based rate options Custom energy profiles for Energy Efficiency Demand Response

Financial Benefits

Reduced equipment and maintenance costs Reduced support expenses Faster outage restoration Improved inventory management
(69)

Advanced Metering Infrastructure

Digital hardware and

software

Interval data measurement

capability

Two-way remote

communications

(70)

AMI in Modern Grid vision

Advanced Metering Infrastructure, National Energy Technology Laboratory, U.S Department of Energy, Office of Electricity Delivery and Energy Reliability, February 2008

(71)

Basic AMI architecture

Customer

Data

Collection

Communication

Network

Utility/ Third Party

Data Reception and Management

Data Transmission

Network

(BPL,PLC, RF,

Public Networks)

AMI Host

server

Meter Data

Management

System

(MDMS)

Electricity Meter

Gas Meter

(72)

AMI communication architecture

Advanced Metering Infrastructure, National Energy Technology Laboratory, U.S Department of Energy, Office of Electricity Delivery and Energy Reliability, February 2008

(73)

AMI security issues

Cleveland, F.M.; , "Cyber security issues for Advanced Metering Infrastructure (AMI)," Power and Energy Society General Meeting - Conversion and Delivery of Electrical Energy in the 21st Century, 2008 IEEE , vol., no., pp.1-5, 20-24 July 2008.

(74)

Conclusion

Cyber-Physical Security of Power Grid is a national priority

Smart Grid Security = Info Sec + Infra Sec + Application Security

Defense-in-Depth & End-to-end Security & Attack-resilient Systems

Cyber-Physical Security Testbeds & Experimentations

Standards development and Industry adoption are critical

Education and workforce development are very important

Synergistic collaboration between Industry-University-National Labs

(75)

THANK YOU …

Acknowledgements

:

U.S. National Science Foundation (NSF)

U.S. Department of Homeland Security (DHS)

U.S. Department of Energy (DOE)

U.S. NSF IU/CRC Power Engr. Research Center (PSERC)

Iowa State Univ., Electric Power Research Center (EPRC)

Graduate Students

:

Aditya Ashok (ISU)

Collaborator

s:

Prof. Chen-Ching Liu, Washington State University (WSU)

Prof. Venkat Ajjarapu, Iowa State University (ISU)

Dr. Adam Hahn, MITRE

Dr. Jianhui Wang, PNNL

Dr. C. W. Ten, Michigan Tech.

Professional

:

http://powercyber.ece.iastate.edu http://cnslab.snu.ac.kr/twiki/bin/view/Main/Research (http://ics-cert.us-cert.gov (http://www.nerc.com http://www.ferc.gov/eventcalendar/Files/20070423091846-EPRI%20-%20Advanced%20Metering.pdf

References

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