Control system including PLC cybersecurity

Control system including PLC cybersecurity

1. Cyber Security Solutions
For <Client Name>
Cyber Security Issues &
Securing Control Systems

2. Power Grid Communications & Control Systems
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InternetControl Systems

3. Agenda
•High-Level
–Industrial Control Systems and Cyber Security Issues
–Securing Control Systems such PLC
•Detailed
–Security Issues in Industrial Control Systems
–Today’s Threats
–Securing Control Systems

4. A Control System
Sensor(s) +
Actuator(s) +
Controller(s)

5. Types of Industrial Control Systems (ICS)
Supervisory Control And Data
Acquisition (SCADA)
Automation
Programmable Logic
controller (PLC)
Distributed Control
Systems (DCS)

6. Historical ICS
•Proprietary
•Complete vertical solutions
•Customized
•Specialized communications
–Wired, fiber, microwave, dialup, serial, etc.
–100s of different protocols
–Slow; e.g. 1200 baud
•Long service lifetimes: 15–20 years
•Not designed with security in mind

7. Third Party
Controllers,
Servers, etc.
Serial, OPC
or Fieldbus
Engineering
Workplace
Device Network
Firewall

Services
Network
Third Party
Application
Server
Application
Server
Historian
Server
Workplaces
Enterprise
Optimization
Suite
Mobile
Operator
Connectivity
Server
Control
Network
Redundant
Enterprise Network
SerialRS485
Modern ICS Trends
IP
Internet
Enterprise
Network

8. Technology Trends in ICS
•COTS (Commercial-Off-The-Shelf) technologies
–Operating systems—Windows, WinCE, embedded RTOSes
–Applications—Databases, web servers, web browsers, etc.
–IT protocols—HTTP, SMTP, FTP, DCOM, XML, SNMP, etc.
–Networking equipment—switches, routers, firewalls, etc.
•Connectivity of ICS to enterprise LAN
–Improved business visibility, business process efficiency
–Remote access to control center and field devices
•IP Networking
–Common in higher level networks, gaining in lower levels
–Many legacy protocols wrapped in TCP or UDP
–Most new industrial devices have Ethernet ports
–Most new ICS architectures are IP-based

9. New IP-Based Industrial Control Systems
•ODVA (Rockwell)
•Profinet
•Foundation Fieldbus HSE
•Telvent
•ABB 800xA
•Honeywell Experion
•Emerson DeltaV
•Yokogawa VNET/IP
•Invensys Infusion
•Survalent
•IP to the Control Network or even Device Network
•Not all are fully compatible with “ordinary IP”

10. Security Risks to Modern ICS
•COTS + IP + connectivity = many security risks
•All of those of Enterprise networks and more
Worms and Viruses Legacy OSes and applications
DOS and DDOS impairing availability Inability to limit access
Unauthorized access Inability to revoke access
Unknown access Unexamined system logs
Unpatched systems Accidental misconfiguration
Little or no use of anti-virus Improperly secured devices
Limited use of host-based firewalls Improperly secured wireless
Improper use of ICS workstations Unencrypted links to remote sites
Unauthorized applications Passwords sent in clear text
Unnecessary applications Default passwords
Open FTP, Telnet, SNMP, HTML ports Password management problems
Fragile control devices Default OS security configurations
Network scans by IT staff Unpatched routers / switches

11. When ICS Security Fails
•Loss of production
•Penalties
•Lawsuits
•Loss of public trust
•Loss of market value
•Physical damage
•Environmental damage
•Injury
•Loss of life
•USSR pipeline explosion, 1982
•Bellingham pipeline rupture, 1999
•Queensland sewage release, 2000
•Davis Besse nuclear plant infection, 2003
•Northeast USA blackout, 2003
•Browns Ferry nuclear plant scram, 2006
$$$.$$

12. ACM CCS Tutorial
Nov. 2009
So How Do We Secure
Industrial Control Systems?

13. Defense in Depth
•Perimeter Protection
–Firewall, IPS, VPN, AV
–Host IDS, Host AV
–DMZ
•Interior Security
–Firewall, IDS, VPN, AV
–Host IDS, Host AV
–IEEE P1711 (AGA 12)
–NAC
–Scanning
•Monitoring
•Management
IDS Intrusion Detection System
IPS Intrusion Prevention System
DMZ DeMilitarized Zone
VPN Virtual Private Network (cryptographic)
AV Anti-Virus (anti-malware)
NAC Network Admission Control

14. Internet
Enterprise Network
Control Network
Field Site Field Site
Field Site
Partner
Site
VPN
VPN
FW
FW
IPS
IDS
IT Stuff
Scan
AV
FW
IPS
P1711
FW
AV
Host IPSHost AV
Proxy
Host IDSHost AV
IDS
Scan
NAC
NAC 62351
Log Mgmt
Event Mgmt
Reporting
50000 Foot View
IT Stuff
VPN

15. ACM CCS Tutorial
Nov. 2009
Security Issues in
Industrial Control Systems

16. Availability, Integrity and Confidentiality
•Enterprise networks require C-I-A
–Confidentiality of intellectual property matters most
•ICS requires A-I-C
–Availability and integrity of control matters most
–control data has low entropy—little need for confidentiality
–Many ICS vendors provide six 9’s of availability
•Ensuring availability is hard
–Cryptography does not help (directly)
–DOS protection, rate limiting, resource management, QoS,
redundancy, robust hardware with high MTBF
•Security must not reduce availability!

17. DoS and DDoS Attacks
•Denial of Service (DoS) attack overwhelms a system
with too many packets/requests
–Exhausts TCP stack or application resources
–Defenses include connection limits in firewall
•Distributed Denial of Service (DDoS) attack
coordinates a botnet to overwhelm a target system
–No single point of attack
–Requires sophisticated, coordinated defenses
–Weapon of choice for hackers, hacktivists, cyber-extortionists
•DoS, DDoS particularly effective when Availability is
critical, i.e. against ICS

18. Fragile ICS Devices
•Many IP stack implementations are fragile
–Some devices lockup on ping sweep or NMAP scan
–Numerous incidents of ICS shut down by uninformed IT staff
running a well-intentioned vulnerability scan
•Modern ICS devices are much more complex
–Some IEDs include web server for configuration and status
–More lines of code leads to more bugs
–Modern IEDs require patching just like servers

19. Unpatched Systems
•Many ICS systems are not patched current
–Particularly Windows servers
–No patches available for older versions of windows
•OS and application patches can break ICS
–OS patches are tested for enterprise apps
•Uncertified patches can invalidate warranty
•Patching often requires system reboot
•Before installation of a patch:
–Vendor certification—typically one week
–Lab testing by operator
–Staged deployment on less critical systems first
–Avoid interrupting any critical process phases

20. Limited use of Host Anti-Virus
•AV operations can cause significant system disruption
at inopportune times
–3am is no better than any other time for a full disk scan on a
system that operates 24x7x365
•ICS vendors only beginning to support anti-virus
–Anti-virus is only as good as the signature set
–Signatures may require testing just like patches
•AV may be losing ground in enterprise deployments
–impact on hosts, endpoint security not getting better
–virus writers have learned to test against dominant AV
•application whitelisting can be a good alternative
–enumerate goodness rather than badness

21. Poor Authentication and Authorization
•Machine-to-machine comms involve no “user”
•Many ICS have poor authentication mechanisms
and very limited authorization mechanisms
•Many protocols use cleartext passwords
•Many ICS devices lack crypto support
•Sometimes passwords left at vendor default
•Device passwords are hard to manage appropriately
–Often one password is shared amongst all devices
and all users and seldom if ever changed
–This is happening AGAIN in Smart Meter deployments!

22. Poor Audit and Logging
•Many ICS have poor or non-existent support for
logging security-related actions
–Attempted or successful intrusions may go unnoticed
•Where IDS logs are kept, they are often not reviewed
•Various regulatory requirements are driving some
change in this area
–NERC—North American Electric Reliability Corporation
–FERC—Federal Energy Regulatory Commission
–Sarbanes Oxley and PCAOB (Public Company Accounting
Oversight Board)
–FISMA—Federal Information Security Management Act

23. Unmanned Field Sites
•Many unmanned field sites
•Many with dialup access
•Some with high-speed connectivity to control center
•Most with poor authentication and authorization
backdoor to the
control center!

24. Legacy Equipment
•Much legacy equipment
•Usually impossible to update to add security features
•Difficult to protect legacy communications
–but see IEEE P1711 for serial encryption
•Password protection is weak
•Little or no audit and logging

25. Unauthorized Applications
•Unauthorized apps installed on ICS systems can
interfere with ICS operation
•Many types of unauthorized apps have been found
during security audits
–Instant messaging
–P2P file sharing
–DVD and MPEG video players
–Games, including Internet-based
–Web browsers

26. Inappropriate Use of ICS Desktops
•Web browsing from HMI can infect ICS
–Browser vulnerabilities
–Downloads
–Cross-site scripting
–Spyware
•Email to/from control servers can infect ICS
–Sendmail and outlook vulnerabilities
•Disk storage exhaustion can crash OS
–Storage of music, videos

27. Little or No Cyber Security Monitoring
•internal monitoring is essential to detect low profile
compromises
–IDS
–port scanning
–vulnerability scanning
–system audit
•without internal monitoring don’t know whether
systems have been compromised

28. Requirement for 3rd Party Access
•Firmware updates and PLC, IED programming are
sometimes done by vendor
–Many ICS have open maintenance ports
–Infected vendor laptops can bring down ICS
•Partners may require continuous status information
–Partner access is often poorly secured
–Partner channels can serve as backdoors
•3
rd
parties may include:
–ISO, transmission provider or grid neighbor,
equipment vendor, emissions monitoring service or agency,
water level monitoring agency, vibration monitoring service,
etc.

29. People Issues
•ICS network often managed by “Control Systems
Department”, distinct from “IT Department” running
enterprise network
–ICS personnel are not IT or networking experts
–IT personnel are not ICS experts
•Majority of control systems workforce is
older and nearing retirement
–Few young people entering this field
–Few academic programs

30. Harsh Environments
•Temperature
•Vibration
•Dust
•Humidity
•Electrical
Transients

31. Attack Vectors into Control Systems
Includes Infected
Laptops and Is Growing
Source: 2003–2006 data from Eric Byres, BCIT

32. Security Assessments on ICS
•Various groups perform security assessments and
penetration tests on ICS (generally under NDA)
–Idaho National Labs
–Sandia National Labs
–N-Dimension Solutions
–Other private organizations
•Vulnerability assessments always uncover problems
•For penetration tests, we always get in
–Not a question of “if”, but “how long”

33. Other Issues
•Unusual physical topologies
•Many special purpose, limited function devices
•Static network configurations
•Multicast
•Long service lifetimes

34. For More Information ...
•See Smart Grid Cyber Security Strategy and
Requirements, NISTIR 7628, www.nist.gov/smartgrid
–particularly Appendices C and D

35. ACM CCS Tutorial
Nov. 2009
Today’s Threats

36. Hiroshima, 2.0 – Cyberspying of the
US Electric Grid (April 09)
Cyberspies penetrate electrical grid (April 09)
'Smart Grid' vulnerable to hackers (March 09)
CIA: Hackers Have Attacked Foreign Utilities
(Jan 2008)
President Obama: securing the electric infrastructure
is a national security priority (June 09)
Smart Grid Security Frenzy: Cyber War Games,
Worms and Spies in Smart Grid (June 09)
earth2tech.com
Intense Media Visibility on the Cyber Security Issue

37. Limited Information About Incidents
•Little information sharing about actual attacks
–BCIT incident database has about 30 incidents per year vs.
100s of thousands of incidents per year in CERT database
–Few cyber attacks on ICS for which details are public
•Little information sharing about actual vulnerabilities
–some are not easily or rapidly fixed
–assessments are done under NDA
•Difficult to estimate risk
–Difficult to demonstrate ROI for security spending
•But… lots of data about significant financial losses in
enterprise and e-commerce
–Why would control systems be immune?

38. Accidents Happen ...

39. Attacks Can Cause Similar Results
INL National Lab Aurora Demonstration, March 2007

40. Regulators provide Smart Grid Stimulus Funding
criteria - cyber security is mandatory (June 09)
FERC releases Smart Grid Policy - cyber security
mandatory for Utility rate recovery (July 09)
Strengthened Cyber Security Standards Approved for
North American Utilities (May 09)
AMI-SEC working group developed security
requirements for AMI
AMI-SEC Task Force
NIST developing interoperability and security standards for
Smart Grid
Ontario Green Energy Act Drives Smart Grid With Security
(May 09)
Cyber Security Regulatory Requirements

41. ACM CCS Tutorial
Nov. 2009
Securing
Control Systems

42. Adversaries
•Script kiddies
•Hackers
•Organized crime
•Disgruntled insiders
•Competitors
•Terrorists
•Hactivists
•Eco-terrorists
•Nation states

43. How an Attack Proceeds—Step #1
Internet
Modem Pool
Web
Server
Email
Server
Business
Workstation
Data
Historian
Engineering
Workstation
FEP
RTU Control
System
Network
Enterprise
Network
Database Server
Domain Name
Server (DNS)
enterprise
Firewall
ICS
Firewall
Attacker
IED
IED
Web
Server
Management
Console HMI

44. How an Attack Proceeds—Step #2
Internet
Modem Pool
Web
Server
Business
Workstation
Data
Historian
Engineering
Workstation
FEP
RTU Control
System
Network
Enterprise
Network
Domain Name
Server (DNS)
enterprise
Firewall
ICS
Firewall
Attacker
IED
IED
Web
Server
Management
Console HMI
Email
Server
Database Server

45. How an Attack Proceeds—Step #3
Internet
Modem Pool
Web
Server
Business
Workstation
Data
Historian
Engineering
Workstation
FEP
RTU Control
System
Network
Enterprise
Network
Domain Name
Server (DNS)
enterprise
Firewall
ICS
Firewall
Attacker
IED
IED
Web
Server
Management
Console HMI
Email
Server
Database Server

46. How an Attack Proceeds—Step #4
Internet
Modem Pool
Web
Server
Web
Server
Business
Workstation
Data
Historian
Management
Console HMI
Engineering
Workstation
FEP
RTU Control
System
Network
Enterprise
Network
Domain Name
Server (DNS)
enterprise
Firewall
ICS
Firewall
Attacker
IED
IED
Vendor Web
Server
Email
Server
Database Server

47. How an Attack Proceeds—Step #5
Internet
Modem Pool
Web
Server
Web
Server
Business
Workstation
Data
Historian
Management
Console HMI
Engineering
Workstation
FEP
RTU Control
System
Network
Enterprise
Network
Domain Name
Server (DNS)
enterprise
Firewall
ICS
Firewall
Attacker
IED
IED
Vendor Web
Server
Email
Server
Database Server

48. How an Attack Proceeds—Step #6
Internet
Modem Pool
Web
Server
Web
Server
Business
Workstation
Data
Historian
Management
Console HMI
Engineering
Workstation
FEP
RTU Control
System
Network
Enterprise
Network
Domain Name
Server (DNS)
enterprise
Firewall
ICS
Firewall
Attacker
IED
IED
Email
Server
Database Server

49. How an Attack Proceeds—Step #7
Internet
Modem Pool
Web
Server
Web
Server
Business
Workstation
Data
Historian
Management
Console HMI
Engineering
Workstation
FEP
RTU Control
System
Network
Enterprise
Network
Domain Name
Server (DNS)
enterprise
Firewall
ICS
Firewall
Attacker
IED
Email
Server
IED
Database Server

50. Defending ICS
•Separate control network from enterprise network
–Harden connection to enterprise network
–Protect all points of entry with strong authentication
–Make reconnaissance difficult from outside
•Harden interior of control network
–Make reconnaissance difficult from inside
–Avoid single points of vulnerability
–Frustrate opportunities to expand a compromise
•Harden field sites and partner connections
–mutual distrust
•Monitor both perimeter and inside events
•Periodically scan for changes in security posture

51. Internet
Enterprise Network
Control Network
Field Site Field Site
Field Site
Partner
Site
VPN
VPN
FW
FW
IPS
IDS
IT Stuff
Scan
AV
FW
IPS
P1711
FW
AV
Host IPSHost AV
Proxy
Host IDSHost AV
IDS
Scan
NAC
NAC 62351
Log Mgmt
Event Mgmt
Reporting
50000 Foot View
IT Stuff
VPN

52. Logical Overlay on SP99 / Purdue Model of Control
Site Business Planning and Logistics Network
Batch
Control
Discrete
Control
Supervisory
Control
Hybrid
Control
Supervisory
Control
Enterprise Network
Patch
Mgmt
Web Services
Operations
AV
Server
Application
Server
Email, Intranet, etc.
Production
Control
Historian
Optimizing
Control
Engineering
Station
Continuous
Control
Terminal
Services
Historian
(Mirror)
Site Operations
and Control
Area
Supervisory
Control
Basic
Control
Process
Control
Zone
Enterprise
Zone
DMZ
Level 5
Level 3
Level 1
Level 0
Level 2
Level 4
HMI HMI

53. Logical Architecture
•Enterprise Zone contains typical business systems
–Email, web, office apps, etc.
•DMZ provides business connectivity
–Contains only non-critical systems that need access to both
Control and Enterprise Zones
–Enforces separation between Enterprise and Control Zones
–Consists of multiple functional sub-zones
•Separated by Firewall, IPS, Anti-Virus, etc.
•Control Zone demarcates critical control systems
–Consists of multiple functional sub-zones
•Internally protected by Firewall, IDS, Anti-Virus, etc.

54. How NOT to connect Control / Enterprise
•Dual-homed server
•Dual-homed server with Host IPS / AV
•Router with packet filter ACLs
•Two-port Firewall
•Router + Firewall combination
•See NISCC Good Practice Guide on Firewall Deployment for
SCADA and Process Control Networks, NISCC and BCIT, Feb
2005

55. Web
Services
Operations
Application
Server
Historian
Mirror
DMZ
DMZ—Logical View
Patch
Mgmt
AV
Proxy
Terminal
Services
No Direct
Traffic
Emergency
Disconnect
Emergency
Disconnect
Multiple
Functional
Sub-Zones
VPN
IPS
Scan
FW
AV
Host AV
Proxy
Host IPS
IDS
IDS

56. DMZ Design Principles
•DMZ contains non-critical systems
•Multiple functional security sub-zones
•Traffic between sub-zones undergoes firewall (& IPS or IDS)
•DMZ is only path in/out of Control Zone
•Default deny for all firewall interfaces
•No direct traffic across DMZ
•No control traffic to outside
•Limited outbound traffic from Control Zone
•Very limited inbound traffic to Control Zone
•No common ports between outside & inside
•Emergency disconnect at inside or outside
•No network management from outside
•Cryptographic VPN and Firewall to all 3
rd
party connections

57. DMZ Implementation (1)
DMZ LAN 3
DMZ LAN 4
DMZ LAN 2
NAT
Routing
FW
IPS
Security
Appliance
With
Multiple
Ports
DMZ/Control
Interconnect
WAN/LAN
Enterprise
LAN
Anti-Virus
Proxy
Host IPS / Anti-virus

58. DMZ Implementation (2)
dot1q
trunkDMZ VLAN 3
DMZ VLAN 4
DMZ VLAN 2
NAT
Routing
FW
IPS
VLAN
Security
Appliance
VLAN-capable
L2 switch
DMZ/Control
Interconnect
WAN/LAN
Enterprise
LAN
Anti-Virus
Proxy
Host IPS / Anti-virus
NOT L3!

59. DMZ Implementation
•Sub-zones implemented by physical LANs or VLANs
–Physical LANs require multi-port Security Appliance
–VLANs require:
•VLAN-capable Security Appliance and Switch
•anti-VLAN hopping protections on switch and FW
•NO L3 (routing) on switch
•FW implements policy between
–DMZ LANs, Enterprise Zone, Control Zone
•Anti-virus proxy controls outbound HTTP and/or FTP
access to enterprise or Internet resources
•Host IPS and/or Host Anti-virus protects DMZ servers

60. Remote Access
DMZ
AAA
Server
Certificate
Authority
Terminal
Services
DMZ/Control
Interconnect
WAN/LAN
Enterprise
LAN
Remote Access Pool
Remote
Access
VPN

61. Remote Access
•Security Appliance terminates Host-to-site VPN into
remote access pool
–IPSEC VPN, SSL VPN, PPTP VPN
•Authenticates user via:
–AAA server, LDAP, Active Directory, etc.
–Can enforce use of multi-factor hardware token
•Time-varying password tokens for vendor access
•Clients use VNC, Citrix, or Remote Desktop (RDP) to
connect to Terminal Server
•Then VNC, Citrix, RDP, or Control System Apps to
Control System Servers

62. Control Zone—Logical View
Batch
Control
Discrete
Control
Supervisory
Control
Hybrid
Control
Supervisory
Control
Production
Control
Historian
Optimizing
Control
Engineering
Station
Continuous
Control
Site Operations
and Control
Area
Supervisory
Control
Basic
Control
Process
Control
Zone
Level 3
Level 1
Level 0
Level 2
HMI
HMI
DMZ

63. Control Zone Design Principles
•Multiple functional security sub-zones
•Firewall and IDS between sub-zones
•Minimal number of connections to DMZ
•Control Zone independent of DMZ, Enterprise
–Separate Security Appliance from DMZ
–Separate Time Server
–Separate AAA
–Allows emergency disconnect from DMZ
•Cryptographic VPN and Firewall to all offsite IP connections
(Field Site or Partner)
•IEEE P1711 for all offsite serial ICS connections
•Host IDS, Host AV, or app whitelisting where feasible
•Management only from management zone

64. Control Zone Implementation—Hierarchical
•Fast routing between
VLANs via L3 switch
•ACLs between VLANs
but no Stateful Firewall
Level 1
Level 2
Level 3
Control
Zone
dot1q Trunks
L3
L3
L2 L2
QoS, Shaping, Policing
Port Security
Gigabit
10/100
DMZ/Control Interconnect WAN/LAN
SPAN
IDS
Scan
FWFW
Host IDS
Host AV

65. Control Zone Implementation—Ring
•Ring reduces wiring for linear
sites like power dams
•but spanning tree can have
problems with large rings
Level 1
Level 2
Level 3
Control
Zone
dot1q Trunks
L3
L3
L2 L2
QoS, Shaping, Policing
Port Security
Gigabit
10/100
DMZ/Control Interconnect WAN/LAN
SPAN
IDS
Scan
FWFW
Host IDS
Host AV

66. Firewall
IDS/IPS
Client VPN
Proxy
Network AV
Host IDS/IPS
NAC
Site-to-site
VPN
DMZ
Perimeter Protection in Utilities

67. IDS
Port Scan
Vuln Scan
Firewall
NAC
SCADA VPN
Firewall
SCADA VPN
Port Scan
IDS
Interior Protection in Utilities

68. Log
Analyze
Report
Compliance
Managed
Security
Monitor, Log, Analyze, Report

69. •Planning, processes, procedures, physical security, etc. are also
important
•NERC CIP Regulatory Requirements provide reasonably good
guidance in this area:
•CIP-001: Sabotage Reporting
•CIP-002: Critical Cyber Asset Identification
•CIP-003: Security Management Controls
•CIP-004: Personnel & Training
•CIP-005: Electronic Security Perimeters
•CIP-006: Physical Security
•CIP-007: Systems Security Management
•CIP-008: Incident Reporting & Response Planning
•CIP-009: Recovery Plans for Critical Cyber Assets
See www.nerc.com -> Standards -> Reliability Standards -> CIP
Beyond Network Security

70. Summary
•Today’s ICS are mix of
modern and legacy
–vulnerabilities due to both
lack of security design in
legacy and security issues
in newer equipment
•Defense in depth is essential
–both perimeter (DMZ) and
interior security are crucial
•Regulation and government
action is driving change
•Smart Grid must be
designed with strong
security

71. ACM CCS Tutorial
Nov. 2009
Thanks!
[email protected]

72. Standards Efforts
•NERC CIPs
•NIST Smart Grid Interoperability Standards Project
•NIST SP800-82
•NIST SP800-53
•NIST PCSRF Protection Profiles
•AMI-SEC
•ISA SP99
•ODVA
•IEEE P1711 (AGA 12) -- serial SCADA encryption

73. A Few References
•www.nist.gov/smartgrid
•Securing Your SCADA and Industrial Control
Systems, Version 1.0, DHS, ISBN 0-16-075115-8
•Guide to SCADA and Industrial Control System
Security, NIST SP800-82
•ISA99 Industrial Automation and Control Systems
Security, www.isa.org/MSTemplate.cfm?
MicrositeID=988&CommitteeID=6821
•AGA 12/IEEE P1689 SCADA Encryption Standard,
scadasafe.sf.net