How to Prevent OT Ransomware Attacks: A Comprehensive Guide
OT ransomware attacks are on the rise. Learn proven strategies to protect your industrial systems, minimize downtime, and recover quickly.
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With the recent deluge of ransomware articles discussing risks, likelihood, payment options, and proposed solutions, it’s a good idea to take a step back to see where you stand with regard to preparedness, response, and recovery.
If you’ve had a risk or vulnerability assessment in the last several years, your organization was likely advised to take steps to help prevent and prepare for large-scale malware/ransomware events. Managing cyber risk or being “prepared” is much more than writing documents or installing technology, but fundamentally it is the result of operationalizing all activity that involves people, processes or technology (PPT). This equates to effective risk management and reduced impact should an event occur. For example:
Imagine, Monday morning as the plant begins to execute a start-up after a weekend shutdown, a flurry of tech support tickets and escalations begin to stack up. According to your last audit, there is an ad hoc process to restore a backup and recover from a single system failure, but this seems out of the ordinary, and you intuitively begin to suspect the worst. What now?
You wonder: Are my backups any good? How do I stop the spread? How do I plug the holes and get control of my assets and their users? What are my assets? Who do I need to call? Who will help me resolve the issue? Too many questions and too little time.
The awareness and training aspects of being prepared can be overwhelming, especially if you want the closest simulation, but for an initial smoke test, I believe a rudimentary skit can be devised to illustrate gaps in your organization’s processes, resources, training, and even technology. Tabletop exercises do not need to be “hacker” orientated, don’t require elaborate props or expensive third-party trainers and platforms, and needn’t be limited to just the security team. With a little time and effort, they can be made effective and accessible to a wider audience of stakeholders.
Executing low-cost ransomware or cyber-event tabletop (TTX) or paper-based training has several benefits:
Based on my experiences creating technical simulations from real data such as the S4 ICS Detection Challenges, the principal components in creating a skit can be simplified when a straightforward event needs to be explored:
Using those phases, let’s start by creating and facilitating awareness events that include technical and non-technical participants.
This step entails the creation of a summary scenario that outlines the whole exercise. This can be crafted by an individual or by a team with relevant understanding of the critical functions of the organization and their overall technology and security posture. The framing is an outline that describes an initial hypothesis and activities for the event within scope. For example, a frame may be built using the following elements:
If we can flesh out all of these areas, we’re on our way to creating an informative exercise. I’ll illustrate framing with an example: A large-scale asset owner (MarineCo) operating a maritime port.
Risk Manager (RM) from MarineCo has been watching the news and heard about the Maersk ransomware incident. RM’s company is a $100M company with profits tightly correlated to the organization running smoothly. Any disruption to product moving in or out of the facility has a string impact on both the company’s bottom line and on the local economy. RM knows that the team is aware of this risk from several audit findings, but he wants to know if the others in the organization are prepared for a massive outage that would likely occur in the wake of a ransomware attack. RM is also aware that many MarineCo systems run on antiquated software, leverage end-of-life operating systems, and suffer from subpar network and user management.
RM frames the incident using these statements:
Then RM arrives at this scenario:
“If the organization faced an aggressive ransomware incident that was spreading quickly from a vulnerable and compromised system, could we manage it as I’ve been promised, communicate to our customers during a disruption, and recover efficiently – even to a degraded state?”
RM would the move to the next phase: The scenario.
Beginning with the framing materials, we need to scope out the scenario much the way an author or playwright defines their story. First, we need to know:
We need to draft the scenario in a play-by-play manner. It can be linear or multi-pathed – like a choose-your-own-adventure book. The simplest of the two options is a linear storyline, but often reality likes to add its own dose of surprises so it’s best to have multiple paths considered, and a few predefined complications to add at times.
For example:
or
The overall event of course needs to be eventually scripted (this is in the implementation phase), but during the composure phase, an approach that looks similar to the table of contents for a technical manual might suffice:
The idea is to ensure that processes that are in scope will be enacted at some point, all roles are impacted, escalation paths are noted, and even fringe activities are covered during the envisioned scenario. For a first attempt, it’s best to keep things simple and have a manageable group of perhaps seven or eight individuals.
With the scenario has been outlined, it’s time to implement the exercise in its entirety. In addition to being the playwright, you’ll also be serving as producer, director, prop master and observer. The script may cover all of al the roles, but it is the responsibility of the producer to set up the scenario with sufficient context to capture the audience’s attention or deliver a message. Whatever the effect, a good scenario needs believable data.
Implementing a scenario has a time factor that cannot be understated. It’s one thing to find enough time to get everyone in the room, another to cross all scenarios or gaps, and yet another to raise awareness for gaps early on while everyone involved is intently focused on the task at hand.
It’s great to test the processes end to end and have varying amounts of realistic data, but if you cannot implement a plausible scenario within a reasonable time frame, the impact of such a training exercise will be limited.
As an example, during the S4x19 S4 ICS Detection Challenge, we created a gigantic set of data under strict NDA to mimic a large faux mining facility located in Eastern Canada. The attack had plenty of noise, some real attacks, and an endgame. The data set was over 130GB in network traffic and the participants were well versed in OT cybersecurity. But despite the lead time for the participants, the main objective of the attackers was missed.
My goal was to see where the participants and their tools would fall short. I wanted to challenge their confidence in their tools and chase rabbits through a labyrinth because during most incidents, defenders have too much data or not enough time or are generally dealing with the consequences after the fact. To be fair, all parties fared reasonably well, but my point was to explain that even with the greatest tools and minds, the limited detection surface would have only been a single piece of the puzzle.
In the MarineCo scenario, you need to keep in mind all of the pieces. There will likely be conversations, processes to be found, responsibilities assigned, challenges to be added. But the event needs to be flexible enough for re-use, if possible, and completable within a single sitting.
The final script needs to contain all the elements with believable roles, relevant screenshots or simulated tooling, props and organization artifacts handy, OT facts such as shared passwords or other common behaviors, and clear start and endpoints.
Now that we have the frame, composed elements, and the implemented attack all in one, we need to execute. I believe that being in the same room helps establish trust and bring light to groups that often do not interact. I even sometimes ask them to switch sides
Regardless, the execution phase is primarily about:
In addition to the execution phase, a very important piece to keep in mind is the role of the mediator, and also any recordings. You may have organizational policies and concerns either for privacy or other situational factors such as sensitive data.
Regardless of any of the actions, frustrations, or even the observations, it is important to consider exercises such as simulating a wide-spread ransomware attack as a training tool. It is not a “finger-pointing” exercise or criteria for someone to be disciplined or removed. Rather, it should be viewed as guidance to help individuals, groups and the company at large fare better during an incident.
The last piece of an exercise involves the collection of insights into how the organization is performing in terms of preparedness. Generally, most organizations rate themselves on cybersecurity maturity via a matrix of controls, but rarely are those controls truly tested end to end,. The summation of the exercise often results in a number of surprises. At this final stage, it is important to:
Real-world incidents in IT or OT require all hands to be present. An event with limited scope, however, can be simulated with minimal investment and can quickly highlight the gaps in cybersecurity capability, particularly if the organization does not consistently apply cybersecurity basics. Through the combination of simulating a ransomware event across people, processes, and technology, organizations can improve their chances to defend against a ransomware attack, limit the impact, find value in their technology investments, and create organizational change.
Simulated attacks and tabletop exercises represent significant tools for reducing risk and bolstering defenses in modern ICS environments. But they’re not the only arrows in the defender’s quiver. Maximizing OT security maturity requires planning and practice coupled with exhaustive asset inventories, well-crafted policies, robust controls and a unified platform that offers 360-degree visibility into all aspects of ICS security assessment, defense, response and recovery.
To learn more:
Take a deep dive into all things OT security including what it is, how it works and where to start when building an effective OT/ICS security program.
Read our case study detailing one industrial firm’s journey to NIST CSF-based security maturity leveraging the powerful combination of Verve Security Center and our expert VIP Services.
See how Verve’s endpoint management capabilities compare head-to-head with other OT/ICS security assessment, protection and response methodologies.
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