Vulnerability Scanning: Types, Limitations, and Selecting an Effective Tool

Vulnerability scanning uses automated tools to identify known software vulnerabilities in an organization’s environment. Vulnerability scanners identify applications running within the environment and check them against the list of Common Vulnerabilities and Exposures (CVEs). Any matches are included in the final report for remediation.

The Importance of Vulnerability Scanning

Vulnerability scanning is important because it provides an organization with insight into the various vulnerabilities in its infrastructure that an attacker might target. Since vulnerability scanners look for CVEs, any vulnerability they identify is publicly disclosed and may be actively targeted by cybercrime groups.

For example, when major vulnerabilities like Log4j were publicly disclosed, they were promptly added to the list of vulnerabilities that scanners searched for. Companies could then use these tools to assess their level of vulnerability to this new threat and identify the systems that require patches and updates to protect them against exploitation.

As software vulnerabilities become more common, vulnerability scanning is more important than ever. Companies need visibility into these evolving threats to protect themselves against data breaches and other cyberattacks.

Types of Vulnerability Scanners

Vulnerability scanners are designed to identify potential vulnerabilities in a wide range of software. Some common types of vulnerability scanners include:

  • Network: Network vulnerability scanners assess network infrastructure, such as routers, firewalls, and switches, for potential security risks. These include open ports, weak/default passwords, and other common problems.
  • Web Application: Web application vulnerability scanners look for common vulnerabilities in an organization’s public-facing websites. This includes security risks such as SQL injection (SQLi) and cross-site scripting (XSS).
  • Database: Database vulnerability scanners look for vulnerabilities in database management systems. These security gaps pose a potential threat of breaching sensitive or valuable data.
  • Host-Based: Host-based vulnerability scanners focus on one or more particular hosts. They look for missing patches, configuration issues, and out-of-date software.
  • Cloud: Cloud vulnerability scanners are tailored to cloud environments. They identify potential vulnerabilities in containerized applications, virtualized environments, and other cloud-based workloads.

In addition to the various targets of vulnerability scanners, vulnerability scans can also be performed in various ways. Some of the main distinguishing factors include:

  • Internal vs. External: Vulnerability scans can be run from inside or outside the organization’s network perimeter. These may identify different vulnerabilities and are designed to emulate external and internal threats.
  • Credentialed vs. Noncredentialed: Vulnerability scanners may also offer the option to perform scans with knowledge of one or more sets of account credentials. This helps an organization detect vulnerabilities that could be exploited by an attacker with a greater level of access to its network.
  • Intrusive vs. Nonintrusive: Most vulnerability scanners won’t exploit identified vulnerabilities; however, this can lead to false positive detections. Some security scanning tools offer vulnerability validation by exploiting the vulnerabilities they identify and verifying the actual risk that they pose.

Challenges of Vulnerability Scanning

Vulnerability scanning can be a useful tool, but it has its limitations. Some common challenges associated with vulnerability scanning include:

  • Visibility: Vulnerability scanners can only identify potential security gaps in assets that they know exist. Security teams can face challenges in asset identification that might create a false sense of security.
  • False Positives: Vulnerability scanners generally don’t attempt to exploit the vulnerabilities that they identify. This means that they commonly generate large volumes of false positives when they misidentify a vulnerability, or a vulnerability that they detect can’t actually be exploited.
  • Configuration Challenges: Vulnerability scanners can be configured in various ways, such as allowing a credentialed scan or specifying the set of assets to scan. If a scanner is misconfigured, it may not perform a complete scan.
  • Diverse Environments: Modern corporate networks include a diverse range of IT assets, including servers, cloud infrastructure, Internet of Things (IoT) devices, and mobile devices. Complete coverage across all asset types is essential for a full view of the organization’s digital attack surface.
  • Vulnerability Prioritization: Vulnerability scanners commonly prioritize their findings using the Common Vulnerability Scoring System (CVSS). However, CVSS scores don’t accurately reflect the risk that a vulnerability poses to the organization and can result in the misallocation of remediation resources.

How To Choose a Vulnerability Scanning Tool

Choosing the right tool is essential to manage an organization’s exposure to software vulnerabilities. Some key factors to consider when selecting a vulnerability scanner include:

  • Asset Support: A vulnerability scanner should offer support for scanning a wide range of IT assets, including the various types that are present within an organization’s IT environment.
  • Scanning Capabilities: A vulnerability scanner should be able to perform various types of scans, including both credentialed and noncredentialed scans to identify as many vulnerabilities as possible.
  • Vulnerability Prioritization: A scanning tool should offer prioritization to rank its findings based on the threat that they pose to the business.
  • False Positive Minimization: A tool should generate a minimal number of false positive detections since these waste resources and can draw focus away from more significant, real threats.
  • Frequent Updates: A vulnerability scanner should perform frequent updates to ensure that it is capable of detecting the latest vulnerabilities.
  • Scalability: A scanning tool should be scalable and capable of inspecting an organization’s entire IT environment for potential threats.
  • Automation: The vulnerability scanner should allow automated scans — or ideally continuous monitoring — to ensure that security teams have up-to-date security visibility.
  • Usability: Vulnerability scanning tools should be easy to use to minimize the risk that misconfigurations introduce visibility and security gaps.

Transitioning From Vulnerability Management to Exposure Management

Vulnerability scanners can be useful tools, but even the best of them will likely produce a large list of vulnerabilities after a scan. While this may seem like a good thing, it’s not if the majority of these are false positives that pose no real risk to the business. Only about 1% of vulnerabilities discovered in the last decade were exploited in the wild, meaning that remediating the other 99% is a waste of time and resources.

A better approach is to make the transition to exposure management, which takes an attacker-centric approach to mapping an organization’s internal and external digital attack surfaces. Instead of looking for all vulnerabilities, exposure management focuses on threats that pose a real risk to the business. This results in a smaller collection of findings that all are exploitable and have real business impacts, rather than vulnerability management’s long list of questionable findings.

IONIX’s threat exposure management platform provides security teams with complete visibility into their real attack surface and enables them to fix only those threats that are both urgent and important. To learn more about how to reduce your attack surface with IONIX, sign up for a demo.