How do you assess the security risks of your network design?

To assess the security risks of a network design, identify assets such as data, hardware, and software, then analyze potential threats like cyberattacks, unauthorized access, and data breaches. Understanding the relationship between assets and threats helps create a comprehensive security strategy for the network.

Primary tool for identifying & classifying assets is the configuration management database (CMDB) which also becomes a good help desk repository for faster customer response. Having location of assets also speeds up local removal from the network if malware surfaces, preventing propagation.

Identify your assets by having a CMDB that is current, owned and up-to-date. Identifying threats involve completing threat modelling exercise for stand alone assets and assets that interface or integrate with each other

I like to talk in Biz Speak when talking Cyber to C Suite Leaders - identify everything & everyone you have, then protect all of them, then detect attacks on any of them, then react to those attacks, then recover. Seems to work. NIST says so :)

Begin by cataloging your assets—data, devices, systems, and services—classified by their value, sensitivity, and criticality. Identify potential threats such as hackers, malware, natural disasters, and human errors, estimating their likelihood and impact.

I’ve seen firsthand how improper network segmentation can lead to security breaches. For example, during an assessment for a financial services company, we discovered that their critical systems were not adequately isolated from the rest of the network. This left them vulnerable to lateral movement attacks. By restructuring their network topology and implementing stronger access controls, we significantly reduced their attack surface. Additionally, ensuring that devices are regularly updated and patched is key to minimizing vulnerabilities. In one case, a client's network was compromised due to outdated firmware on a critical device, which could have been prevented with proper configuration management.

Setting up good Macro Segmentation for North-South traffic movement is just as important. One firewall is not always the solution, break up the traffic with multiple devices using that route direction.

Review the structure and parameters of your network. Ensure segments are isolated, devices updated, encryption strong, and monitoring tools effective. Identify vulnerabilities in the topology and configuration that could expose assets to threats.

Analyzing your network topology is essential to pinpoint vulnerabilities in the architecture itself. In my experience, this includes reviewing segmentation, zoning, and data flow pathways for weaknesses that could allow lateral movement or unauthorized access. Ensure that your configurations are not only secure but also align with the principle of least privilege. A zero-trust architecture is increasingly effective in modern designs, where each component is assumed compromised unless verified. Periodic reviews of your topology against current attack trends help you anticipate potential security gaps.

Penetration Testing tools have become more automated & allow for one individual to setup & launch a large network multinode scan which can provide a very detailed results output. This can then be utilized to make adjustments as needed to tighten down your security posture.

Good tools are as good as those that utilize them. If they are properly configured they will utilize UEBA & alert on unexpected activities. An example is account lockouts, especially with Admin accounts. Admins don't casually mistype the password.

Utilize frameworks like the NIST Cybersecurity Framework to guide your assessment across functions: identify, protect, detect, respond, and recover. Employ tools like vulnerability scanners and network analyzers to detect and evaluate risks.

Leveraging structured frameworks such as NIST Cybersecurity Framework or ISO/IEC 27001 is highly beneficial for consistency and thoroughness. I recommend integrating automated tools like vulnerability scanners and penetration testing software to complement these frameworks. From my experience, tools like these streamline the identification of misconfigurations, patching needs, and unknown vulnerabilities. Combining a framework with continuous monitoring tools enables you to create a dynamic, real-time view of your risk landscape, which is crucial for fast adaptation to emerging threats.

When it comes to prioritizing and mitigating risks, the focus should be on those that pose the greatest threat to your critical assets. In a real-world scenario, I worked with an e-commerce platform where we identified several vulnerabilities through a penetration test. Instead of attempting to fix everything at once, we prioritized the vulnerabilities that could lead to data breaches, as this would have the most significant impact on the business. We implemented strong encryption for sensitive data and enhanced firewall configurations to prevent unauthorized access. By taking a strategic approach to risk mitigation, we were able to protect the most valuable assets first, ensuring business continuity while addressing other issues over time.

Prioritizing and mitigating risks is crucial in cybersecurity and network design. This strategic approach involves identifying and addressing the most critical threats efficiently. By focusing resources on the most impactful risks based on likelihood and potential consequences, organizations enhance the security of sensitive assets. Mitigation strategies, such as implementing robust controls and training, contribute to resilience against evolving cyber threats. This targeted approach ensures cost-effective risk management, aligning security measures with specific business priorities and reducing overall vulnerability.

Working on this area within the confines of ZTA is critical to ensure meeting the President's Executive Order 14021 ZTA which has a due date in 2027 for all federal agencies since it is such a complex task. Starting with your Crown Jewels and working down means you have at least protected the most valuable assets as soon as possible as you work toward full and complete protection.

Rank risks by severity and urgency. Focus on high-threat risks and implement controls such as firewalls, encryption, and incident response plans to mitigate them based on your risk tolerance.

Once risks are identified, prioritization is key. I often emphasize that not all risks are equal—using a matrix to weigh likelihood versus impact can clarify which threats demand immediate attention. Resources are finite, so focus mitigation efforts where they will make the most significant difference. Consider measures such as implementing micro-segmentation, applying rigorous patch management, or strengthening encryption for high-risk areas. Ultimately, the goal is to address the highest-impact vulnerabilities without exhausting your team or budget.

You will full documentation for communication of risks to auditors for SOCs, HIPPA, PCI, etc. anyway. A good GRC (Governance, Risk & Compliance) system will help facilitate this given appropriate access as needed. This will keep it all in a single repository & easy to maintain.

Record and report findings and recommendations clearly. Use consistent formats and convey information via reports, dashboards, or meetings to stakeholders such as management and staff.

Risk documentation isn’t just for compliance; it’s a strategic tool for ongoing security management. In my experience, clearly documented risks help keep all stakeholders, from IT staff to executives, aligned on the security posture and priorities. This transparency fosters better decision-making, especially when changes in budget or business operations are on the table. Make sure documentation is accessible and regularly updated to reflect any new threats or changes in mitigation efforts. Communication is key—effective briefing of risks to all levels of the organization ensures informed actions and buy-in.

One thing I find helpful is having a trusted third party provide a second opinion on an organizations analysis of risks. Automated tools such as vulnerability scans can provide valuable insight, but frequently lack context and can get those closest to a system hyper focused on the wrong risks and mitigations. This can lead to a gross waste of resources.

The cybersecurity landscape evolves rapidly, which is why regular reviews of your risk assessments are essential. I’ve found that establishing a cadence for reviewing and updating your network’s security, whether quarterly or in response to specific triggers like new vulnerabilities, helps ensure your risk posture remains current. Utilize real-time threat intelligence feeds to proactively update your assessment, and consider incorporating cyber drills or simulations to stress test your network against potential attacks. Continuous improvement should be the cornerstone of your risk management strategy.

Regularly monitor and evaluate the risk assessment process. Update the assessment based on new information, assets, threats, or controls. Utilize audits and feedback to refine the process.

Beyond these steps, don’t overlook the human element in network security. I often remind clients that even the most secure network can be compromised by user error or insider threats. Regular training, access control reviews, and creating a culture of cybersecurity awareness are critical elements of a holistic security approach. Additionally, consider third-party risks – external vendors or partners with access to your network can introduce vulnerabilities that you don’t directly control. Establish strict protocols for vendor access and regularly audit their security practices to safeguard your network further.

Share real-world examples and stories. For instance, a company that recently updated its network to segment critical data from general access areas saw a significant reduction in breach attempts. Incorporating practical experiences can offer valuable insights.

I have always followed 3 simple rules as a CIO/CISO: Only allow Trusted Entities (TE) onto your network Only allow those TEs to use Trusted Devices (TDs) One allow those TDs to run Trusted Applications (TAs) So, if only a TE can use a TD which can only run a TA, your Network is fairly secure. Now you can add to this as much as you like but your foundation is solid.

In addition to the structured approach to risk assessment, it’s crucial to foster a culture of proactive security. One example from my career involved creating a cross-functional security task force within a large organization. This team was responsible for regularly reviewing and updating security protocols, as well as educating employees on emerging threats. This initiative not only improved the organization's security posture but also empowered employees to contribute to the overall safety of the network. Furthermore, involving stakeholders from different departments ensured that security measures aligned with business objectives, creating a more resilient and agile response to potential threats.