With industries and critical infrastructure sectors increasingly dependent on interconnected systems, it becomes essential to reconsider the conventional practice of granting trust to entities upon entering the network’s perimeter. The repercussions of potential breaches in OT environments extend significantly beyond the immediate incident. As a result, it is critical to implement a more flexible and forward-thinking OT Security strategy.
Zero Trust, How and Why
Zero Trust Security is a cybersecurity framework and approach based on the mantra “Never trust, always verify.” In a Zero Trust model, trust is not automatically presumed for any individual, equipment, or software, regardless of their position in the corporate network.
On the contrary, trust is constantly verified, and privileges to resources are approved based on thorough proof and identification of the entity’s identity, the security posture of the device, and the reasons for the access request.
Departing from Perimeter Based Security
Historically, many organizations depended on conventional perimeter security, which involved establishing a firm outer boundary to protect their internal network. Trust was often implicitly granted once individuals were inside this boundary.
The limitations of perimeter security became apparent as the threat landscape grew with more sophisticated cyberattacks. Cyber threats can originate both from inside and outside the network. Once they infiltrate, attackers can move laterally, rendering traditional perimeter defenses ineffective.
Zero Trust deviates from the perimeter-based security strategy. It acknowledges that threats may originate from any location and that all parties trying to obtain permission to use resources must achieve and sustain credibility.
The Unique Nature of OT Environments
It is vital to emphasize OT and IT environments’ distinct challenges and vulnerabilities. These challenges and vulnerabilities highlight the significance of introducing Zero Trust Security in OT settings.
Legacy Infrastructure
Several OT systems were developed and implemented decades ago and are still used today. These legacy systems are frequently deficient in contemporary security features and not created with a focus on cybersecurity. As a result, they are susceptible to common exploits and may pose difficulties to secure.
High Risk Environments
Failures or breaches in OT systems can have serious consequences. OT is in charge of many manufacturing processes, and OT systems should be continuously operational and highly available. This requirement can make maintenance and updates on security more difficult because impairment to activities can have serious consequences in addition to financial losses.
Systems Interdependency
OT systems are increasingly linked to IT networks for monitoring and remote access. This connectivity opens new attack vectors because threats can move from IT to OT or vice versa.
Complexity and Heterogeneity
OT environments commonly include a mix of devices and technologies from various vendors. Because of this complexity, it can be challenging to sustain a reliable security approach.
<<Also Read: Advanced Cybersecurity Threats- The Latest Generation Of Viruses And Malware>>
Best Practices OT Environments and Zero Trust
Because OT systems are critical, adopting Zero Trust Security in an OT environment requires a deliberate and systematic approach.
- Begin by compiling an all-inclusive inventory of all OT assets and cataloging them according to criticality and function. The initial stage involves precisely understanding what requires protection.
- Segregate the OT network into disparate regions that have differing security levels. This segmentation limits crosswise movement for potential threat actors and alleviates the impact of security incidents.
- Put strong identity and admission controls, such as solid verification and authorization.
Before authorizing access, verify all users, devices, and applications.
- Follow the fundamental concept of least privilege. Users and equipment should only have access to the resources necessary for their roles, and privileges must be kept to a bare minimum.
- The requirement for remote access in operational environments has solved several operational challenges. Nonetheless, remote access has introduced new cybersecurity challenges that need addressing to protect sensitive operational assets.
- Create an OT-specific incident response plan.
- Educate OT personnel on best practices for cybersecurity and Zero Trust principles.
- Regularly review and update Zero Trust policies and configurations to adapt to the evolving OT environment and changing threats.
Conclusion
Zero Trust is a crucial model for safeguarding OT environments that takes an open and flexible approach to address the challenges and vulnerabilities that the vital infrastructure presents. Companies are encouraged to take proactive measures to improve OT security and decrease the probability of cyber-attacks and disruptions.
