Vulnerability prioritization: The ultimate guide (2024)

Agenda

1. Understanding vulnerability prioritization
2. How vulnerability threats are categorized
3. Why vulnerability prioritization matters
4. 6 different vulnerability prioritization methods
5. Vulnerability exposure analysis
6. Data-driven decision making
7. Implementing effective solutions
8. Strategies for improvement
9. Case studies and success stories

Understanding vulnerability prioritization

Vulnerability prioritization is a vital step in vulnerability management and CTEM. Simply put, it puts security vulnerabilities in the order in which they should be addressed.When dealing with tens or hundreds of thousands of potential threats, prioritization is crucial to getting any work done with the limited resources available.

How vulnerability threats are categorized

Deciding what is or isn’t an important threat is no easy task. Luckily, there are methods to categorize the threats.

Asset value

Not all assets in a network are equally important to cyber security—those open to the public or on multiple devices are at a critical status due to the scale of access they allow. It’s crucial to create a value scale for assets and the impact of a breach.

This asset value scale can be built based on who is responsible for the asset, its role within the business, and its worth (financial or operational).

When it comes to vulnerability prioritization, understanding which assets are more interconnected within the network will help determine which assets need to receive the greatest level of protection from potential threats.

Business impact

Vulnerability management prioritization is about protecting a business from every attack vector, and some vulnerabilities will affect a business more than others. When prioritizing vulnerabilities, it’s crucial to consider the scale of impact an attack on a vulnerability will have on the business.

CVSS score

The Common Vulnerability Scoring System (CVSS) scoring system is a free tool to help score how severe an attack on a vulnerability will be. It’s made up of three metrics: Base metrics, temporal metrics, and environmental metrics.

Base metrics

CVSS-based metrics are based on exploitability, scope, and impact. Exploitability takes into account:

• Attack vector
• Attack complexity
• Privileges required
• User interaction

Scope focuses on whether one vulnerability can spread to others—like a cold spreading to other people. An example is if exploiting one vulnerability gives access to an operating system where more vulnerabilities can be exploited.

Impact is calculated through:

• Availability: If the attack will cause the original owners to lose access to the system.
• Confidentiality: The amount of data the attack exposes.
• Integrity: The ability to change any information.

Temporal metrics

These metrics relate to vulnerabilities that change over time. Temporal metrics are measured through:

• Exploit code maturity: How likely a vulnerability is to be exploited based on current techniques.
• Remediation level: If there is already a patch or workaround readily available.
• Report confidence: The confidence of the level of concern about the exploitation of a particular vulnerability.

Environmental metrics

Environmental metrics are meant to change the base metrics based on different security requirements and modifications.

Security requirements are similar to the asset value already mentioned. Asset value focuses on how critical an asset is to a business. Modified base metrics refer to whether a cyber security team has already put mitigations in place and altered the original severity of a vulnerability.

Ideally, vulnerability prioritization should be based on all of the above, providing a clear picture of where one’s organization is most at risk.

Why vulnerability prioritization matters

So far, in 2024, the National Vulnerability Database (NVD) has reported more than 248,000 new common vulnerabilities and exposures (CVE). Additionally, the Cybersecurity and Infrastructure Security Agency (CISA) reports that hackers can exploit a vulnerability within 15 days after finding it.

That’s why vulnerability prioritization matters. Threat actors work fast, and your security team needs to work faster—but they only have so many resources. This is why you need to prioritize the vulnerabilities that will most affect your business.

Just one cyber attack can result in:

• Damaged reputation
• Financial loss
• Legal battles
• Non-compliance fees
• Operational disruptions
• Stolen personal information
• System access loss

6 different vulnerability prioritization methods

Now it’s time to decide how to prioritize vulnerabilities—depending on your needs, you can follow more than one method.

1. Focusing on CVSS scores

Some IT teams prefer to prioritize vulnerabilities purely based on their CVSS score, which can be 0-10, depending on the metrics discussed above.

2. Using the CISA KEV database

CISA offers a Known Exploited Vulnerabilities (KEV) list to create open communication between cyber security teams to pool resources. KEV allows teams to evaluate their priorities based on what vulnerabilities have already been publically exploited.

3. Focusing on what can be fixed right away

Sometimes, resources are scarce, and getting anything fixed is better than nothing. This method of prioritization focuses on what can be done with the available resources.

4. Using EPSS

The Exploit Prediction Scoring System (EPSS) helps teams estimate the likelihood of an attack on various vulnerabilities. It gathers vulnerability and exploitation information from various sources and scores the probability of exploiting a vulnerability in the next 30 days.

5. Focusing on business impact

Some cyber security teams prioritize vulnerabilities based on how severely they can affect an organization’s operations instead of the probability of an attack or other vulnerability factors. These companies have to weigh the likelihood of a crippling attack on infrastructure more heavily than lesser attacks, even if they are more likely to occur.

6. Measuring against required resources

This prioritization method places a high value on making use of available resources. This method can be deployed to optimally use a company’s security resources instead of focusing solely on the severity of vulnerabilities.

Vulnerability exposure analysis

IT security teams also have to consider the kind of exposure to your entire infrastructure each vulnerability gives attackers. For example, if one device was compromised, would that vulnerability give a hacker access to the entire network as soon as the device is used?

When categorizing and prioritizing vulnerabilities, it’s important to analyze the types of potential exposure possible. Even if the vulnerable data is low priority, the amount of exposure could make the vulnerability high on the priority list.

You need a tool that will consider this aspect of prioritization along with other methods to generate the most accurate report on vulnerability prioritization.

Data-driven decision making

Making vulnerability prioritization decisions requires taking in a lot of data and then making a decision. How does a cyber security team get any actual work done if they spend all day reading information and making decisions?

They need a way to pool all their vulnerability data into one place so decision-making is easier. The Vulcan Cyber platform allows teams to understand risks, communicate risks, and then reduce risks.

Our platform can consolidate data from all your attack surfaces and tell you what is needed to mitigate risks—whether it’s a patch for an application or system, a workaround, or a new script. You can customize risk prioritization based on your business needs and impacts.

Through all this, decisions and actions can be taken quickly, allowing teams plenty of time to minimize the risk of exploitation.

Implementing effective solutions

Now that you understand how to prioritize vulnerabilities, how can you find and organize them effectively?

Deciding what prioritization method works for your team

As discussed, there are a variety of methods to use for prioritizing vulnerabilities, but you need to choose the right method—or combination of methods that work best—for your team and organization.

Cataloging assets

If you haven’t already, it’s time to organize the various assets your organization uses. This will make identifying vulnerabilities easier as new threats appear. Assets include:

• Applications
• Cloud-based resources
• Datasets
• Devices
• Employees
• User Identification Applications
• Networks
• Programs
• Security controls
• Software
• VPNs

Continuous monitoring and feedback

The world of cyber security is ever-changing, and so are its threats. Proper vulnerability management prioritization is not a one-time thing: It requires constant vigilance. Ensure that your team is current with the most recent threat landscape and known cyber attacks.

Run regular scans to locate any new vulnerabilities and ensure the current mitigations are up to date. You should also run regular software and firmware updates to minimize potential exposures.

Strategies for improvement

Once everything is in place, you can improve your strategies in several ways.

Create KPI benchmarks

It’s always helpful to set goals for improvement through key performance indicators (KPIs). Examples of KPIs include reducing severe vulnerabilities by a specific date, lowering the average time spent on organizing vulnerabilities or improving the speed at which vulnerabilities are handled.

Provide cyber security training to non-IT employees

Sometimes, vulnerabilities are people who don’t realize they’re exposing the company to threat actors. Provide other company members with basic cyber security training, such as detecting suspicious activity or reminding them not to click on unfamiliar links.

Also, offer contact information to them so they can ask questions if a potential security problem occurs.

Case studies and success stories

The Vulcan Cyber ExposureOS platform can help with your vulnerability prioritization needs.

Faster vulnerability processes

One travel service and insurance enterprise was using manual processes that were taking too long, allowing threat actors plenty of time to get into their systems. After adopting the Vulcan Cyber platform, they were able to automate their cyber security processes using our platform, which led to more than a 75% reduction in the mean time to remediation.

Easier risk identification

Wealthsimple experienced significant growth within their business and found that deciding how to prioritize vulnerabilities was difficult at their scale. Partnering with Vulcan Cyber allowed them to streamline the process by integrating the Vulcan platform with other security tools without disrupting processes already in place.

Better utilization of resources

What happens when a company is too busy with product launches and doesn’t have time to neutralize vulnerabilities? That’s what Mandiant was struggling with—they just didn’t have the resources for potential threats when real products needed to be monitored.

Working with Vulcan Cyber, Mandiant used the platform’s tools to prioritize vulnerabilities with little manual effort. This let the team focus on what was most important: Products and actual threats.