Vulnerability Assessment: How It Works and Tips for Success

What Is a Vulnerability Assessment?

Vulnerability assessment is the process of defining, identifying, classifying, and prioritizing vulnerabilities in computer systems, applications, and network infrastructure. Vulnerability assessments provide organizations with the knowledge, awareness, and risk context they need to understand and respond to environmental threats.

A vulnerability assessment process aims to identify threats and risks. It often involves the use of automated testing tools, such as network security scanners, and the results are recorded in vulnerability assessment reports.

While organizations of all sizes can benefit from some form of vulnerability assessment, large enterprises and organizations exposed to ongoing attacks will benefit the most. A security breach could give hackers access to IT systems and applications, so businesses need to identify and fix vulnerabilities before they can be exploited — this can be achieved by a comprehensive vulnerability assessment and management program.

This is part of a series of articles about vulnerability management.

Why Is Vulnerability Assessment Important?

Vulnerability assessments include a variety of methods, tools, and scanners for finding blind spots or weaknesses in a system or network.

Vulnerability assessments enable security teams to apply a comprehensive and well-defined approach to identify and address security threats and risks to their IT infrastructure, both for existing and evolving threats. It helps close existing gaps in infrastructure, by identifying threats and weaknesses early and taking remedial action.

Vulnerability assessments also play an important role in ensuring organizations are compliant with cybersecurity regulations and Health Insurance Portability and Accountability Act (HIPAA) and Payment Card Industry Data Security Standard (PCI DSS) guidelines.

Vulnerability Management vs. Vulnerability Assessment

Vulnerability management and vulnerability assessment work differently to achieve similar objectives — helping organizations address and resolve security vulnerabilities. Vulnerability management is the overall process, while a vulnerability assessment is the first step within this process.

What is vulnerability management?

Vulnerability management is the entire lifecycle process, an ongoing program that incorporates various phases, including vulnerability assessment, prioritization, and remediation. A vulnerability management program typically leverages multiple data sources to continuously assess and reassess the current state of services and software.

The role of vulnerability assessment

A vulnerability assessment involves using scanning tools to gather information from devices on a network, such as software versions, and compare the information to known software vulnerabilities. Organizations typically run scans at set times and scheduled intervals for patching and upgrades.

Vulnerability assessment vs. management

Vulnerability assessment offers an overview of the software portfolio. Vulnerability management provides continuous real-time intelligence, reporting, and remediation guidance.

What Is the Vulnerability Assessment Process?

1. Vulnerability Identification

This process discovers and makes a list of all vulnerabilities found in an IT infrastructure. It typically involves manual penetration testing (pentesting) and automated vulnerability scanners. A vulnerability scanner can analyze networks, computers, and web applications for known vulnerabilities using various sources, like the Common Vulnerabilities and Exposures (CVE) glossary. Pentesting helps fill in the gaps by finding unknown exploitable vulnerabilities.

2. Vulnerability Analysis

After identifying vulnerabilities in an environment, you need to find the components that allow the vulnerability and the root cause of various security weaknesses. A security assessment process classifies the severity of each vulnerability, identifies remediation options, and uses the organization’s risk management strategy to determine whether to accept, mitigate, or remediate.

3. Risk Assessment

This step involves prioritizing vulnerabilities, typically by using a vulnerability assessment tool to assign a rank or severity to all identified vulnerabilities. A risk assessment report typically accounts for various factors of the affected system, including its composition, the data it stores, its impact on business continuity, the ease of attack or compromise, compliance regulations, and more.

4. Remediation

During this process, teams fix the security issues identified as unacceptable during the risk assessment phase. Vulnerability management systems typically provide recommended remediation guidance for common security vulnerabilities. For example, it might recommend installing a readily-available security patch or replacing hardware.

5. Mitigation

Mitigation occurs when you cannot remediate. It involves reducing the impact of an exploit or minimizing the likelihood that a vulnerability can be exploited. Mitigation steps vary depending on the organization’s risk tolerance and budget. However, common mitigation strategies include introducing new security controls, encryption, or replacing software or hardware.

Vulnerability Assessment Best Practices

Comprehensive Initial Assessment

Vulnerability assessments should start with a comprehensive preliminary assessment. At the heart of this step is the asset discovery process, which identifies all assets to be scanned.

The early discovery of assets to scan for vulnerabilities is a significant challenge. Many enterprises lack sufficient visibility into their hybrid multicloud infrastructure. This can include cloud systems built by development teams without coordinating with central IT.

Additionally, modern websites and web applications rely on complex interactions between internal and third-party resources. For example, many websites load resources from third party services and marketing solutions, which may contain vulnerabilities.

The vulnerability management tooling selected by an organization should provide a way to accurately take inventory of web applications, third-party resources, endpoint devices, and all other assets in the environment.

It should then consider the strategic factors that determine a company's level of risk tolerance for each asset or asset class. Customer-facing applications and public-facing assets should be prioritized. Some digital assets are not sensitive and might require less frequent vulnerability assessments.

Ranking Security Weaknesses

A common problem with vulnerability assessment is that security teams receive lists of hundreds or thousands of vulnerabilities. This can be overwhelming and tedious without a system that adequately defines the importance and severity of vulnerabilities.

Vulnerability assessment solutions should provide a severity rating for the vulnerabilities found to help you prioritize. The basis of these rankings is usually the Common Vulnerability Scoring System (CVSS). However, other contextual information such as knowledge of scanned assets, a company's individual risk profile, and the relevant threat landscape, can also influence the ranking system.

A Practical Plan For Responding to Threats

Ultimately, vulnerability assessment is linked to a company's overall approach to cyber risk management. Therefore, it is important to use the knowledge you have gathered about the organization’s cybersecurity posture to develop actionable threat response plans.

Vulnerabilities discovered during an automated scan can guide a plan for responding to a threat to the vulnerability or the system that discovers it. A remediation strategy should describe who should be involved, or what to do, in case of an incident, and how to prevent incidents in the first place.

Effective Vulnerability Assessment Report

Powerful vulnerability assessment reports allow security teams to effectively and thoroughly address vulnerabilities by directly patching vulnerabilities, changing configurations, or mitigating threats. These reports should be clear and concise, to immediately educate readers about findings and their significance.

A good vulnerability assessment report includes information such as:

• A summary that presents key findings without overwhelming the reader

• A diagram listing the vulnerabilities

• An overview of the tools and methods used during the assessment

The body of the report should be a findings section with a description of each vulnerability, severity, potential consequences of the exploit, and remediation or mitigation recommendations.