Cybersecurity Vulnerabilities in Audiovisual Control Systems and Protocols

By Paul Konikowski, CTS-D

This article orginally published in Commercial Integrator on August 6, 2019.

The Stuxnet and Target attacks have squashed many of the myths about securing industrial control system security.

Wait, you don’t know about Stuxnet, and the Target attack?

  • The Stuxnet Worm, first discovered in 2010, was responsible for damaging approximately 1/5th of the centrifuges in Iran’s nuclear program. The complex malware exploited four zero-day vulnerabilities, and eventually targeted specific programmable logic controllers (PLCs) and supervisory control and data acquisition (SCADA) computers.
  • In 2013, Target’s in-store point-of-sale devices were infected by memory-scraping-malware, which allowed hackers to capture the data stored on magnetic strips of credit/debit cards as they were swiped. The hackers infiltrated Target’s internal systems using the stolen credentials of a third-party HVAC contractor, obtained through an email phishing attack, which also gave them direct access to Target’s payment system.

Myths Surrounding Industrial Control System Security:

Myth #1 – Isolating control systems networks keeps them safe from malicious attacks: FALSE.

In the Stuxnet attack, the SCADA systems and PLCs that controlled the Iranian nuclear centrifuges were air-gapped, theoretically isolating them from the public internet. It is widely believed that the Stuxnet worm was implanted using admin credentials and USB thumb drives on the internal air-gapped computers.

Myth #2 – Highly specialized controllers and industrial control networks are safe from attack due to “security through obscurity”: FALSE.

The Target attackers used custom malware that was unrecognizable by standard anti-virus software, and exploited a previously unknown flaw (a.k.a. zero-day vulnerability) in what was then traditional retailer point-of-sale encryption.

The Stuxnet worm was constructed to look for specific PLC’s, software, and industrial devices. If the worm infected a host computer and did not find the specific systems, it would move on to the next machine, and erase any evidence of itself upon departure.

Myth #3 – Firewalls, Intrusion Detection Systems (IDSs), and Intrusion Prevention Systems (IPSs) effectively protect control system networks from attack: FALSE.

ICS networks are subject to man-in-the-middle attacks, where the hackers capture control system protocol messages that are sent in plaintext in TCP packets.

Once the attackers figure out what is going on, which can take some time and/or knowledge of the industrial process, they can replace the intended plaintext commands with malicious commands that can cause damage.

The firewalls and IDS/IPS system don’t recognize the altered packets as malicious, because they appear to originate from an authorized host, and look like typical control system protocols. Target’s security team received alerts from their Intrusion Detection System, but basically ignored them.

Design with Least Privilege & Least Route

To minimize the chances and impact of an attack on a control system, AV programmers and system designers should employ the principles of Least Privilege (or Use) and Least Route for better industrial control system security.

Least Privilege means that users or services should only be given the minimum access required to do their job. Similarly, the principle of Least Route states that a device should only possess the minimum level of network access that is required for its individual function.

Instead of placing AV devices on open, general-purpose local area networks, AV devices should be placed on their own dedicated, purpose-built networks.

The network switches and routers should be configured using access control lists (ACLs) so that only specific, authorized devices can send traffic inside or outside of the network. VLANs are not an effective security measure.

Air-gapping AV control systems certainly makes them safer, but not completely, and many AV devices are now constantly monitored by internal support staff and/or external AV integrators.

This does not mean that everything in industrial control system security needs to be on the local area network. Many AV controllers have dual network interfaces that allow the AV devices to be placed on a dedicated control subnet, and the AV controller can communicate to the supervisors using the second networks interface via firewall.

This is a good example of Least Route. Technically speaking, network traffic can traverse the two network jacks, but it is difficult.

Figure1and2

If you enjoyed this article, you might like these related posts:

Danger! Logic Bombs in Audiovisual Control Systems

My 3-Tiered Approach to Networked AV Security

Design Principles For Secure AV Systems

Identifying Cyber Attacks, Risks, Vulnerabilities in AV Installations

5 Steps to Better Cyber Risk Management

The Best Data Breach Incident Response Plans Require These Steps

 

Danger! Logic Bombs in Audiovisual Control Systems

So-called Logic Bombs haven’t quite found their way into audiovisual control systems yet, but just wait…The unprepared will suffer.

This article was originally published in Commercial Integrator on July 9, 2019

Logic bombs are a form of malicious code whose effects are purposefully delayed by design. The name “logic bomb” stems from the classic ticking bomb imagery often depicted in James Bond type movies. The logic bomb initially goes unnoticed during its dormant phase, and is triggered by elapsed time, a specific date, or some combination of inputs. Logic bombs are common in computer malware, but haven’t been reported in audiovisual control systems, so you have to use your imagination a little.

Here are a few examples:

  • A logic bomb could be programmed into an AV control system, so that after a projection screen is lowered and raised 100 times, the logic bomb is triggered, and the AV system no longer functions properly.
  • A logic bomb could be set so that it is triggered on a specific date some time in the future.The AV system works fine until July 1, 2020, and then suddenly, it stops working, even if the AV system is rebooted.
  • A logic bomb could also be triggered by a certain combination of inputs.

Let’s say you have a 4-way divide/combine space that is typically separated into 4 rooms, A, B, C and D. The system is tested and works when the rooms are separated or combined into 1. But when you try to divide the rooms into A&B and B&C, it suddenly stops working.

Any permutation of the three examples above could also be combined, making the logic bomb is harder to detect.

Logic bombs in computer systems are often triggered by a certain login. Imagine if every time a particular CEO used a video conference system, it recorded and/or streamed the call to a hidden endpoint.

Who on Earth would do this?

The answer is: anyone with malicious intent.

An external hacker who has infiltrated a business network could replace the audiovisual control system with similar code that includes a logic bomb, which could open a back door for them at a later date, and/or forward logins and other valuable information out through the firewall.

This would make the security breach harder to attribute to a specific IP address or individual.

Another scenario might be a malicious internal attacker. Perhaps an on-prem AV support technician asked for a raise and did not get it.

Once they found a new job elsewhere, the jaded individual could replace the AV control system code with one that included a logic bomb. The logic bomb could be set to go off during a big annual meeting, or gather valuable information that could then be sold to a company’s competitors.

AV integrators could also implement logic bombs to generate unnecessary service calls.

Most AV systems are warrantied for the first year. After a year, the client has an option to continue the service plan on an annual basis. If they don’t have a service plan, the customer has to pay for each service call that is placed.

The best defense against logic bombs are passwords that limit the access to the audiovisual control system code. Any device on the LAN should be locked down using access controls on network switches.

Customers should also demand uncompiled copies of the final AV control system code, and watch the AV integrator upload that code to the AV system at the very end of the project, so they know there are no logic bombs.

LOGIC BOMB in the form of binary code, 3D illustration

If you enjoyed this article, you might like these related posts:

My 3-Tiered Approach to Networked AV Security

Design Principles For Secure AV Systems

Identifying Cyber Attacks, Risks, Vulnerabilities in AV Installations

5 Steps to Better Cyber Risk Management

The Best Data Breach Incident Response Plans Require These Steps

 

My 3-Tiered Approach to Networked AV Security

How should the industry provide a whole culture of networked AV security? It could start with these three steps.

This article was originally published in Commercial Integrator on June 5, 2019

Over the last few years, the audiovisual integration industry has become increasingly more aware of networked AV security concerns, largely due to some vulnerabilities discovered in control system touchscreens and wireless presentation systems. Manufacturers have answered with firmware updates that patch the vulns, and AVIXA released Recommended Practices for Security in Networked AV Systems in July 2018

Despite these efforts, many #AVTweeps are still calling for networked AV security standards and industry leadership. We can’t just sit back and wait for cybersecurity researchers to tell us about the next zero-day vulnerability. We need to take a proactive approach and work together to leverage our knowledge.

So how do we get started?

One idea would be to launch an open group that anyone can join, like the Ad Hoc Committee on Responsible Computing Group, who publishes a regularly updated document called “Moral Responsibility for Computing Artifacts”, more commonly referred to as “The Rules.”

Or we could take a more formal approach and follow the lead of the Payment Card Industry Security Standards Council (PCI-SSC) which is an independent body that was created by major payment card brands.

The PCI-SSC sets the Payment Card Industry Data Security Standard (PCI-DSS).

That approach might work for AV manufacturers, but it might also inadvertently leave out integrators, consultants, distributors, IT professionals, and AV support personnel that work inside of organizations. All of these groups make up the AV industry, and each has their own priorities.

To involve all of these parties while still maintaining some order, I suggest a three-tiered approach:

Cybersecurity Leadership at the Industry Level

At the top tier would be a Cybersecurity Council led by audiovisual industry associations like Avixa and/or NSCA, who would work to develop standards and promote best practices in networked AV security.

The Cybersecurity Council might host annual or bi-annual 1-day or 2-day virtual conferences, where speakers and panel discussions could address market-wide security concerns.

The Council would promote cybersecurity awareness, as well as the adoption of industry-specific cybersecurity frameworks.

Cybersecurity Alliances at the Company Level

At the next tier would be Cybersecurity Alliances, which would be groups of companies that have similar interests and business models.

There could be a Manufacturers’ Alliance, an Integrators’ Alliance, and an End-Users’ Alliance (we will have to think of a better name).

AV consultants and distributors could have their own alliances, or they may fall into one of the other Alliances to keep things simple. The main goal here would be for similar companies to share threat information and strategies, much like the National Cyber Security Alliance (NCSA), who aims to make the internet safer and more secure for everyone.

The Alliances could host quarterly online meetings, but could also alert each other when they are attacked, or when a vulnerability has been discovered, as many AV companies utilize the same OEM technology.

Cybersecurity Teams of Individuals

The third tier would consist of teams of individuals, from any of the above Cybersecurity Alliances, who would focus on specific aspects of cybersecurity.

There could technical teams made up of CIOs, CTOs, programmers, and technicians who focus on recent exploits, risks and vulnerabilities, cloud security, network design, data protection, application development, access controls, forensic analysis, cryptography, incident response, intrusion detection, cyber-physical systems, databases, or web security.

There could also be non-technical teams who would be focused more on laws and regulations, procedures, and policies. They could work together to train employees, update documents, conduct risk and liability assessments, develop industry bug bounty programs, or share ransomware response plans.

The goal of this column is not to dictate what I think should be done, but rather to present a potential framework to use as a basis of discussion. My hope is that individuals within the AV industry will talk to Avixa and/or NSCA at Infocomm or other events, and maybe these ideas will get some traction by 2020.