How To Protect Your Computer From Attack



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Hacking SCADA/SAS Systems Used Techniques, Known Incidents and Possible Mitigations Seminar at Petroleum Safety Authority Norway at 29/11-2006 Christian H. Gresser cgresser@nesec.de

Agenda About NESEC What is SCADA Well-known Incidents IT-Security and control Systems Problems in SCADA security SCADA systems security is different Hacking is easy IT-security in the future Possible solutions Lessons learned NESEC Gesellschaft für angewandte Netzwerksicherheit mbh Seite 2 Hacking SCADA Petroleum Safety Authority V1.2 November 2006

About NESEC Founded 2002 as a system integrator specialized on IT security in Freising (near Munich/Germany) Strong focus on security in production environments Close cooperation with ABB Automation Products, development of security concepts and solutions for ABB customers Security analysis and penetration tests, even in life production, to identify possible threats and rate risks Working solutions to secure production plants and SCADA systems without interruption in production Customers include Munich Airport, Krupp-Mannesmann steel production, Volkswagen, Altana Pharma, and more NESEC Gesellschaft für angewandte Netzwerksicherheit mbh Seite 3 Hacking SCADA Petroleum Safety Authority V1.2 November 2006

SCADA Supervisory Control and Data Acquisition Monitor and control industrial systems Oil and Gas Air traffic and railways Power generation and transmission Water management Manufacturing Production plants Huge threats Massive power blackout Oil refinery explosion Waste mixed in with drinking water NESEC Gesellschaft für angewandte Netzwerksicherheit mbh Seite 4 Hacking SCADA Petroleum Safety Authority V1.2 November 2006

What is SCADA and control systems? The power in your home The water in your home Where the wastewater goes The cereals and milk for breakfast Traffic lights on the way to the office The commuter train control system The phone system to your office The air conditioning in your office building The convenience food in the canteen much, much more NESEC Gesellschaft für angewandte Netzwerksicherheit mbh Seite 5 Hacking SCADA Petroleum Safety Authority V1.2 November 2006

Well-known Incidents NESEC Gesellschaft für angewandte Netzwerksicherheit mbh Seite 6 Hacking SCADA Petroleum Safety Authority V1.2 November 2006

Well-known Incidents Aaron Caffrey, 19, brought down the Port of Houston October, 2003. This is thought to be the first well-documented attack on critical US infrastructure. In August 2003, computer systems of CSX Transportation got infected by a computer virus, halting passenger and freight train traffic in Washington, DC. In 2003, the east coast of America experienced a blackout, while not the cause, many of the related systems were infected by the Blaster worm. Computers and manuals seized 2003 in Al Qaeda training camps were full of SCADA information related to dams and related structures Ohio Davis-Besse nuclear power plant safety monitoring system was offline for 5 hours due to Slammer worm in January 2003 2001, hackers penetrated a California Independent System Operator which oversees most of the state's electricity transmission grid, attacks were routed through CA, OK, and China. NESEC Gesellschaft für angewandte Netzwerksicherheit mbh Seite 7 Hacking SCADA Petroleum Safety Authority V1.2 November 2006

Well-known Incidents In 2000, former employee Vitek Boden release a million liters of water into the coastal waters of Queensland, Australia A Brisbane hacker used radio transmissions in 2000 to create raw sewage overflows on Sunshine coast In 2000, the Russian government announced that hackers succeeded in gaining control of the world s largest natural gas pipeline network (owned by Gazprom) In 1997, a teenager breaks into NYNEX and cuts off Worcester Airport in Massachusetts for 6 hours, affecting both air and ground communications. In 1992, a former Chevron employee disabled it s emergency alert system in 22 states, which wasn t discovered until an emergency happened that needed alerting. NESEC Gesellschaft für angewandte Netzwerksicherheit mbh Seite 8 Hacking SCADA Petroleum Safety Authority V1.2 November 2006

Risks in Production Environments Viruses, Trojans, malicious mobile code 42% of all attacks! Social engineering Denial of service attacks Deficient physical infrastructure Vulnerabilities in the OS and in applications Use of protected/illegal material, private use Hacking and cracking Disasters NESEC Gesellschaft für angewandte Netzwerksicherheit mbh Seite 9 Hacking SCADA Petroleum Safety Authority V1.2 November 2006

Attacker s SCADA Knowledge Ethernet TCP/IP Windows RPC SMB 802.11b HTTP/HTTPS ASCII Unix/Linux/Solaris TFTP SQL Just this is sufficient OPC PLC RTU ModBus IEC 60870 ICCP HMI/MMI S5/S7 Fieldbus IED TASE-2 This is all on the Internet NESEC Gesellschaft für angewandte Netzwerksicherheit mbh Seite 10 Hacking SCADA Petroleum Safety Authority V1.2 November 2006

How does SCADA work? Multi-tier systems Physical measurement/control endpoints RTU, PLC Measure voltage, adjust valve, flip switch Intermediate processing Usually based on commercial OS VMS, Windows, Unix, Linux Communication infrastructure Analog, Serial, Internet, Wi-Fi Modbus, DNP3, OPC, ICCP Human Interface Most attacks happen at this level NESEC Gesellschaft für angewandte Netzwerksicherheit mbh Seite 11 Hacking SCADA Petroleum Safety Authority V1.2 November 2006

Problems with SCADA SCADA = no authentication What is the identity of an automated system? OPC on Windows requires anonymous login rights for DCOM How can policies such as change your password monthly be applied to automated systems running unattended for years? How do you manage rights for each person? SCADA = no patching Systems never needed patches in the past install a system, replace it in 10 years large window of vulnerability NESEC Gesellschaft für angewandte Netzwerksicherheit mbh Seite 12 Hacking SCADA Petroleum Safety Authority V1.2 November 2006

Problems with SCADA SCADA = not connected to the Internet often believed: not interconnected at all found in reality: numerous uncontrolled connections even unconnected networks get connected via dial-in or notebooks from support personnel SCADA = insecure design and implementation simple passwords used by many people and never changed anonymous FTP, Telnet without password access limitations in control software are often not used NESEC Gesellschaft für angewandte Netzwerksicherheit mbh Seite 13 Hacking SCADA Petroleum Safety Authority V1.2 November 2006

SCADA System security is different Risk Impact Risk Management Reliability Performance Security Information Technology Loss of data Recover by reboot Safety is a non-issue Occasional Failures tolerated Beta test in field acceptable High throughput demanded High delay and jitter accepted Most sites insecure Little separation among intranets on same site Focus is central server security Control Networks Loss of production, equipment, life Fault tolerance essential Explicit hazard analysis expected Outages intolerable Thorough quality assurance testing expected Modest throughput acceptable High delay a serious concern Tight physical security Information systems network isolated from plant network Focus is edge control device stability NESEC Gesellschaft für angewandte Netzwerksicherheit mbh Seite 14 Hacking SCADA Petroleum Safety Authority V1.2 November 2006

SCADA System security is different Aspect of IT Anti-virus Lifetime Outsourcing Patching Change Time criticality Availability Security skills and awareness Security testing Physical security Corporate IT widely used 3-5 years widely used frequent (often daily) frequent delays OK outages OK (overnight) fairly good widely used usually secure and manned Process Control IT often difficult / impossible to deploy 5-20 years rarely used for operations slow (required vendor approval) rare critical, often safety dependent 24 / 7 / 365 poor must be used with care often remote and unmanned NESEC Gesellschaft für angewandte Netzwerksicherheit mbh Seite 15 Hacking SCADA Petroleum Safety Authority V1.2 November 2006

Standards for IT-Security in SCADA Standards BS 7799/ISO 17799 ISO 27001 ISA SP99 IEC 62443 (draft) IEC 61784-4 (draft) (IEC SC65c WG13) NIST Process Control Security Requirements Forum (PCSRF) NERC Cyber Security Standard NISSC Practice Guide on Firewall Deployment for SCADA and Process Control Networks NIST Special Publication 800-40 Title Information Security Management Information Security Management Manufacturing and Control Systems Security widely used Digital Data Communications for Measurement and Control Network and System Security System Protection Profiles (SPP) and Protection Profiles (PP) for Common Criteria (ISO 15408) US IT-security standard for power plant operation Firewall Deployment for SCADA and Process Control Networks Procedures for Handling Security Patches Board British Standards Institute / International Organization for Standardization International Organization for Standardization Instrumentation Systems and Automation International Electrotechnical Commission International Electrotechnical Commission National Institute for Standards and Technology North American Electric Reliability Council UK National Infrastructure Security Coordination Centre National Institute for Standards and Technology NESEC Gesellschaft für angewandte Netzwerksicherheit mbh Seite 16 Hacking SCADA Petroleum Safety Authority V1.2 November 2006

Real World Example Claim: We are secure because the oil production network is completely separate from the rest of the corporate network Flaw #1: network diagrams don t match reality It s the desired configuration not the actual configuration Flaw #2: diagram obviously doesn t match reality Dial-in for remote support is in the office network not the production network, how can they connect? Flaw #3: notebooks Notebooks are often used by support personnel to trace problems. Are the secured? Flaw #3: insecure production network No patches, no segmentation, if one systems gets compromised, it can bring down everything NESEC Gesellschaft für angewandte Netzwerksicherheit mbh Seite 17 Hacking SCADA Petroleum Safety Authority V1.2 November 2006

Hacking is easy High Low Intruder Knowledge back doors trojans disabling audits network mgmt. diagnostics Attack session Sophistication burglaries hijacking exploiting known vulnerabilities self-replicating code password guessing packet spoofing sniffers sweepers password cracking Cross site scripting stealth / advanced scanning techniques Staged denial of service attack distributed attack tools www attacks automated probes/scans GUI Attackers 1985 1990 1995 2000 2005 Tools NESEC Gesellschaft für angewandte Netzwerksicherheit mbh Seite 18 Hacking SCADA Petroleum Safety Authority V1.2 November 2006

Hacking is easy High Low Intruder Knowledge back doors trojans disabling audits network mgmt. diagnostics Attack session Sophistication burglaries hijacking exploiting known vulnerabilities self-replicating code password guessing packet spoofing sniffers sweepers password cracking Cross site scripting stealth / advanced scanning techniques Staged denial of service attack distributed attack tools www attacks automated probes/scans GUI Attackers 1985 1990 1995 2000 2005 Tools NESEC Gesellschaft für angewandte Netzwerksicherheit mbh Seite 19 Hacking SCADA Petroleum Safety Authority V1.2 November 2006

Example Hack This example break-in uses only publicly available free software and information Nmap port scanner to identify the target OS (see: http//www.insecure.org/) Nessus vulnerability scanner to identify the missing patches (see: http//www.nessus.org/) Symantec SecurityFocus Vulnerability Database (see: http://www.securityfocus.com/bid/ or: http://www.milw0rm.com/) Metasploit Exploit Framework (see: http://www.metasploit.org/) Everyone can use these tools! NESEC Gesellschaft für angewandte Netzwerksicherheit mbh Seite 20 Hacking SCADA Petroleum Safety Authority V1.2 November 2006

Free Vulnerability Databases 04/04 NESEC Gesellschaft für angewandte Netzwerksicherheit mbh Seite 21 Hacking SCADA Petroleum Safety Authority V1.2 November 2006

Free Vulnerability Databases 28/11 NESEC Gesellschaft für angewandte Netzwerksicherheit mbh Seite 22 Hacking SCADA Petroleum Safety Authority V1.2 November 2006

Free Download of all Tools 04/04 NESEC Gesellschaft für angewandte Netzwerksicherheit mbh Seite 23 Hacking SCADA Petroleum Safety Authority V1.2 November 2006

Free Download of all Tools 28/11 NESEC Gesellschaft für angewandte Netzwerksicherheit mbh Seite 24 Hacking SCADA Petroleum Safety Authority V1.2 November 2006

Tools used in the Live Hack 29/11 Some tools only work well with a Unix operating system, e.g. Nmap and Nessus For the live hacking today we use the following tools: SuperScan4 from Foundstone (a division of McAfee, Inc.) (free download: http://www.foundstone.com/resources/freetools.htm) Metasploit Exploit Framework (see: http://www.metasploit.org/) SecurityFocus Vulnerability Database (a division of Symantec Corp.) (see: http://www.securityfocus.com/bid/ The complete vulnerability scan with Nessus will be skipped due to time restraints NESEC Gesellschaft für angewandte Netzwerksicherheit mbh Seite 25 Hacking SCADA Petroleum Safety Authority V1.2 November 2006

What s in the future Microsoft currently does a good job securing their systems There already is a trend to attack different parts in the operating system backup software and anti-virus because agents are installed on all systems completely new environments production plants It is only a matter of time before automation systems will be attacked A good indicator are the SANS Top 20 Internet Security Vulnerabilities see: http://www.sans.org/top20/ NESEC Gesellschaft für angewandte Netzwerksicherheit mbh Seite 26 Hacking SCADA Petroleum Safety Authority V1.2 November 2006

What s in the future 2006 was the year of application break-ins widespread automated exploits for office applications but also backup software, anti-virus and personal firewalls new and automated attacks against web applications 2007 will be the year of network components exploits for router, switches and all the networking gear Critical infrastructure like DNS will be targeted again 2008 will be the year of embedded and automation systems many issues are fixed, new targets are required these systems are finally connected to the networks NESEC Gesellschaft für angewandte Netzwerksicherheit mbh Seite 27 Hacking SCADA Petroleum Safety Authority V1.2 November 2006

More attacks! Infection Attempts 900M 800M 700M 600M 500M 400M 300M 200M 100M 0 Polymorphic Viruses (Tequila) Mass Mailer Viruses (Love Letter/Melissa) Zombies Denial of Service (Yahoo!, ebay) Blended Threats (Code Red, Nimda, Slammer) Malicious Code Infection Attempts Network Intrusion Attempts 1997 1998 1999 2000 2001 2002 2003 2004 150,000 125,000 100,000 75,000 50,000 25,000 0 Network Intrusion Attempts 2004 CERT NESEC Gesellschaft für angewandte Netzwerksicherheit mbh Seite 28 Hacking SCADA Petroleum Safety Authority V1.2 November 2006

More viruses! NESEC Gesellschaft für angewandte Netzwerksicherheit mbh Seite 29 Hacking SCADA Petroleum Safety Authority V1.2 November 2006

New attack vectors! NESEC Gesellschaft für angewandte Netzwerksicherheit mbh Seite 30 Hacking SCADA Petroleum Safety Authority V1.2 November 2006

Shift in awareness necessary Control systems have become very similar to office environments They need to be treated similar Control systems are interconnected to corporate networks or even the internet They need the same (or even better) protection Shift in security awareness: IT security should be part of the initial design process not an add-on later IT security should be part of the standard maintenance procedures not only after an incident Every employee is responsible for IT security NESEC Gesellschaft für angewandte Netzwerksicherheit mbh Seite 31 Hacking SCADA Petroleum Safety Authority V1.2 November 2006

Awareness is Rising Finally ISS gave a presentation on SCADA Security at the Black Hat Federal Conference in January 2006 They found lot s of problems in widely used software OPC has many buffer overflows OPC over DCOM is often very insecure and while analyzing SCADA systems SCADA systems usually have no authentication SCADA systems are usually not patched You can go to the store and buy a book on pen-testing that will give you all the knowledge you need to cause a widespread power blackout! NESEC Gesellschaft für angewandte Netzwerksicherheit mbh Seite 32 Hacking SCADA Petroleum Safety Authority V1.2 November 2006

Multilayered approach necessary Protecting the infrastructure Block access to sensitive parts of the infrastructure (e.g. rooms, buildings), often referred to as physical security Protecting IT-systems Use anti-virus software and install patches to protect systems from viruses, worms and exploits Protecting networks Use firewalls and filters for network segmentation Protecting applications and data Use encryption and VPNs to protect data from unauthorized access User education Train your employees to use and adopt IT security NESEC Gesellschaft für angewandte Netzwerksicherheit mbh Seite 33 Hacking SCADA Petroleum Safety Authority V1.2 November 2006

Lessons learned IT security is becoming very important Control networks are no longer isolated networks Automation systems are no longer specialized platforms They are new targets They are interesting targets Hacking Tools are easy to use Everybody can attack and break into systems The tools are readily available If you are not protected, you will be hacked There is neither cause to panic nor cause to ignore the issue NESEC Gesellschaft für angewandte Netzwerksicherheit mbh Seite 34 Hacking SCADA Petroleum Safety Authority V1.2 November 2006

References Kevin Poulsen, Slammer worm crashed Ohio nuke plant network, http://www.securityfocus.com/news/6767 SQL Slammer Worm Lessons Learned for Consideration by the Electricity Sector, North American Electric Reliability Council, http://www.esisac.com/publicdocs/sql_slammer_2003.pdf NRC Information Notice 2003-14, Potential Vulnerability of Plant Computer Network to Worm Infection, United States Nuclear Regulatory Commission, http://www.nrc.gov/reading-rm/doc-collections/news/2003/03-108.html Instrumentation, Systems and Automation Society (ISA), Security Technologies for Manufacturing and Control Systems, Technical Report ANSI/ISA-TR99.00.01-2004, ANSI/ISA-TR99.00.02-2004, March/April 2004, http://www.isa.org/ International Electrotechnical Commission, Enterprise Network Control Network Interconnection Profile (ECI), IEC/SC 65C/W 13 Draft v1.04, December 2004 National Infrastructure Security Coordination Centre (NISCC), NISCC Good Practice Guide on Firewall Deployment for SCADA and Process Control Networks, Revision 1.4, February 2005, http://www.niscc.gov.uk/niscc/docs/re-20050223-00157.pdf NIST, Procedures for Handling Security Patches, NIST Special Publication 800-40, August 2002, http://csrc.nist.gov/publications/nistpubs/ NESEC Gesellschaft für angewandte Netzwerksicherheit mbh Seite 35 Hacking SCADA Petroleum Safety Authority V1.2 November 2006

What NESEC can do Expertise in penetration testing of process control networks Working and applicable concepts and solutions to secure production IT environments and PCNs Review of existing security concepts Development of Best Practices for PCNs What can we do for you??? NESEC Gesellschaft für angewandte Netzwerksicherheit mbh Seite 36 Hacking SCADA Petroleum Safety Authority V1.2 November 2006

Thank you very much for your attendance Your questions please Christian H. Gresser NESEC GmbH Lichtenbergstrasse 8 D-85748 Garching Tel.: +49 89 5484-2130 Fax: +49 89 5484-2139 email: cgresser@nesec.de Web: http://www.nesec.de/