Vulnerability Prioritization Strategies for Effective Exposure Management

Part Two of Three: Exposure Management that Drives Tangible Cyber Risk Reduction Outcomes

Exposure management is not a simple task. It involves dealing with a large volume of vulnerability data, prioritizing the most critical issues, and coordinating patching efforts across different teams and stakeholders. How can you ensure that your exposure management strategy is effective and aligned with your business objectives?

In Part One of our Exposure Management blog series, we looked at the challenge of vulnerability detection and talked about the key metrics that indicate effective exposure management. In this post, we will explore various strategies for vulnerability prioritization, emphasizing a holistic approach that goes beyond the use of specific tools or services. We will discuss these strategies in three parts:

• Understanding your environment: knowing what you have and identifying coverage gaps.
• Making sense of the data: putting environmental data and threat intelligence together for highly effective prioritization.
• Taking action: using what you’ve learned to know what to patch, how to patch, and why it’s important, so that you can reduce risk in tangible, provable ways.

Understanding Your Environment: Risk-Based Vulnerability Prioritization Starts at Home

One of the biggest challenges in exposure management stems from a lack of contextualization around detected vulnerabilities. To achieve effective vulnerability prioritization, you must understand each vulnerability’s actual risk to your organization. Not all vulnerabilities are critical (even when the CVSS score says it is), and not all assets are equally important. A vulnerability that may be critical for one organization may be irrelevant for another, depending on the context and the impact of a potential breach.

Effective vulnerability prioritization requires a deep understanding of your environment and the assets that are most critical to your business. But mapping your network topology isn’t enough. Effective asset visibility identifies assets and their dependencies, determines coverage gaps, and assigns each asset a business value or criticality score. By doing so, you can focus your attention on the vulnerabilities that affect your most valuable assets and pose the greatest threat to your business continuity, reputation, and compliance.

Making Sense of the Data: Defining Criticality Beyond the CVSS Score

All too often, vulnerabilities get mis-prioritized – or missed entirely – due to the vast amount of uncontextualized data that gets collected from various sources. Vulnerability scanners, threat intelligence feeds, security advisories, press releases, dark web intelligence… the list goes on. And then there are the Common Vulnerability Scoring System (CVSS) scores attached to Common Vulnerabilities and Exposures (CVEs). These metrics are typically assigned quickly after a CVE is discovered, and then they’re rarely analyzed or updated. While a CVSS score can serve as a starting point, they’re a theoretical measurement that lacks the context required for true prioritization.

So then, how can a team prioritize signals, especially when they don’t have a team dedicated 24x7x365 to filtering out the noise? The answer is contextual analysis. To make sense of the data, you need to look beyond the CVSS score and contextualize your vulnerability findings in terms of risk-based indicators. Some of the most common and easily attainable factors include:

• Asset criticality, or the business value or importance of the asset that is affected by the vulnerability. As discussed above, this metric indicates how severe the impact of a breach would be. No one understands your environment better than you do. Assigning and maintaining asset criticality scores is a vital component of effective risk management and should be a prioritized effort across your organization.
• Exploitability, or the availability and ease of use of exploits for a given vulnerability. This metric indicates the likelihood of a vulnerability’s exploitation in the wild. The exploitability of a vulnerability is often detailed within CVE listings, intelligence feeds, and security advisories.
• Known usage by threat actors, or the evidence of active exploitation or weaponization of a vulnerability by malicious actors. If you have a weaponized or actively exploited vulnerability on one of your systems, you’ll probably want to prioritize patching, especially if found on a high priority asset. Like exploitability, known usage is also found in CVE listings, intelligence feeds, and security advisories.

By combining factors such as these, you can create a risk score for each vulnerability that reflects its actual severity and urgency for your organization. This way, you can prioritize the vulnerabilities that are more exploitable, actively used by threat actors, and pose the most threat to your business. By taking action against them, you can make data-driven decisions that proactively reduce risk to your organization.

Taking Action: Vulnerability Prioritization in a Clear Path Toward Risk Reduction

Once you know what you have in your environment, and you understand the risk to your organization, the final challenge in exposure management revolves around how you act on your data. This may involve patching, mitigating, or accepting the risk, depending on the feasibility and cost of each option. For the purposes of this post, we’re going to focus on patching, as it is often the most effective and preferred way to reduce your exposure and prevent breaches.

It is important to note that patching is not a one-time event, nor is it the function of a single person or team. Patch management is a continuous process that requires coordination and collaboration across different teams and stakeholders, such as IT operations, application owners, security teams, and vendors. To overcome the game of patching whack-a-mole, where you are constantly chasing new vulnerabilities and patches, you need to establish a patch management process that is efficient, scalable, data-driven, and automated – and one that automatically ties into your vulnerability prioritization processes. This means:

• Having a clear and consistent policy for patching, including roles and responsibilities, timelines, and exceptions.
• Using a centralized platform or tool that can automate the patching workflow, from discovery and prioritization to deployment and verification.
• Communicating and collaborating with the relevant teams and stakeholders, ensuring that they are aware of the patching requirements, schedules, and impacts.
• Monitoring and measuring the patching performance, using metrics and dashboards that can track the patching status, progress, and effectiveness.

By following these steps, you can ensure that your patching process is aligned with your exposure management strategy and that you are reducing your cyber risk in a timely and consistent manner.

Putting it All Together

You may be reading this thinking, “that’s great – but where do I get all this data?” Chances are, you already have the data you need. However, that data most likely lives in multiple, disjointed feeds, reports, and dashboards across your various security tools. Once you have identified where you can find all your asset inventories, configuration data, vulnerability scans, threat intelligence feeds, etc., the resulting challenge lies in pulling that data together and making it actionable.

With the right Vulnerability Prioritization platform, you can automatically ingest multi-vector data, including all the feeds noted above, and you’ll gain access to deeper data, including dark web intelligence, and expert analysis provided by your platform vendor.

Automation is the Critical Component for Effective Vulnerability Prioritization

Threat actors don’t work 8 to 5. In fact, they’re more likely to strike when you’re not paying attention. The best solution for risk-based vulnerability prioritization is the integration of an automated platform. You’ll want a solution that continuously ingests and normalizes data from across your existing cybersecurity tools, contextualizes alerts based on your unique environment, and analyzes vulnerabilities against potential exploitability, actual exploitation, and weaponization. With an automated process in place, you’ll gain risk-aware prioritizations and actionable directions for remediation so that you can rapidly reduce risk—and prove it.

Be sure to subscribe and follow us on social media so that you’ll catch the final installment in this three-part series, where we show you how you can prepare for the future of exposure management.