What is Vulnerability Scanning?

Technical Reviewer
Updated: May 29th, 2025
19 mins read
the-complete-guide-to-vulnerability-scanning

A 219% surge in automated scans in 2024 looks impressive—until you realize most teams still don’t know what to do with the results. Scanning without a strategy is noise. The real challenge isn’t running more scans but building the muscle to act on what they reveal. This guide cuts through the automation hype to focus on what actually drives results.

Key Takeaways

  • Vulnerability scanning identifies security flaws across digital assets, but its real value lies in turning findings into action through prioritization and remediation.
  • Effective scanning programs maintain a live risk baseline, scale with infrastructure, and reduce manual effort through automation.
  • Integration with CI/CD pipelines transforms scanning from a reactive task into a proactive part of the development lifecycle.
  • The right tool cuts through noise with deep coverage, real-world exploit simulation, and compliance-ready insights that drive strategic decisions.

Fundamentals

What is Vulnerability Scanning?

Vulnerability scanning is the process of programmatically identifying known security weaknesses across digital assets, such as web applications, APIs, cloud infrastructure, and endpoints, using automated tools. They leverage updated vulnerability databases (e.g., CVE, CWE) for detecting misconfigurations, outdated software, and exploitable flaws, typically through unauthenticated and authenticated scans.

Why is Vulnerability Scanning Important?

Vulnerability Scanning Importance

When systems evolve daily, so does risk; every release, configuration change, or third-party integration can open new doors for attackers. Vulnerability scanning isn’t just a security checkbox but how you keep pace with change.

1. Map Your Exposure

Think of vulnerability scanning as asset intelligence, not just flaw detection, which provides a live map of where your systems are vulnerable across every code push, infrastructure tweak, or third-party update. In a world of instant exploits, visibility is no longer a diagnostic but a defense.

2. Establish a Live Risk Baseline

Vulnerability scanning creates a real-time snapshot of your system’s weakest points, revealing what’s exposed, the severity of the risks, and their location within your environment, i.e., creating a live risk baseline that helps your team prioritize threats and track security drift over time.

3. Enable Scalable, Repeatable Security Hygiene

By automating frequent checks across complex, distributed environments to reduce the reliance on manual reviews, automated scans ensure consistent detection of vulnerabilities across legacy or cloud-native assets while scaling with growing infrastructure.

4. Create Accountability Loops With Engineering

Vulnerability scanning turns invisible risks into visible, trackable issues. Simply put, once vulnerabilities are surfaced, assigned, and time-stamped, they create clear ownership and timelines for remediation. This makes security a shared, actionable responsibility, grounded in real data and continuous feedback.

What is the Primary Purpose of Vulnerability Scanning?

The purpose of vulnerability scanning is to provide continuous visibility into your risk posture. As technology evolves at breakneck speed and teams adopt cloud and microservices, vulnerability scanning becomes foundational to managing risk without compromising innovation. This helps your organization:

  • Shift from tactical to strategic risk management
  • Prioritize what matters to your business
  • Embed security into the development cycle with automation
  • Enhance compliance and business resilience

In practice, a company like a SaaS provider might use vulnerability scanning to prioritize fixes in its core customer-facing services over less critical internal tools, not just to improve security but reduce risk to customer trust and operational uptime, two vital metrics for business continuity.

Types and Methods of Vulnerability Scanning

Types of Scans

Vulnerability scans can be made to target particular areas of your infrastructure; knowing these various types allows you to allocate resources effectively and tackle key risks in an efficient manner. Some common types include:

Scan Type Focus Area What It Detects Use Case / Example
Web App Scanning Front-end logic & code SQLi, XSS, insecure sessions, broken auth, vulnerable libraries Detecting flaws in login forms, dashboards, and form fields
API Scanning API endpoints (REST, SOAP, GraphQL) Broken access control, insecure data flows, weak authentication Securing public/private APIs in SaaS platforms
Network Scanning Routers, firewalls, and internal servers Open ports, unpatched systems, unauthorized access points Securing internal network architecture
Cloud Scanning Public cloud (AWS, Azure, GCP) Misconfigured buckets, weak IAM roles, and open security groups Hardening cloud workloads and infrastructure-as-code setups
Internal Scanning Internal systems within the trusted network Insider-access risks, lateral movement paths Simulating an attack post-breach or from rogue employees
External Scanning Public-facing assets (websites, APIs, IPs) CVEs and misconfigurations are visible to attackers Identifying what attackers see from outside

Types of Vulnerabilities

Awareness-building projects and communities, such as OWASP and NIST, document the most critical vulnerabilities at a given time, publishing lists of the most vital and pervasive threats. These lists are usually followed while checking scanning systems for vulnerabilities.

  • Broken Access Control

    Access control refers to the application of constraints on who can perform a certain action or access certain information. In web applications, access control is usually maintained through authentication and session management.

  • Cryptographic Failures

    Cryptographic failure is a general term that describes a situation where sensitive data can be accessed without proper authorization. It refers to a condition where the data in transit, or at rest, is not secured through encryption.

    Pro Tip: Successful cryptography ensures access control by employing ciphers along with initialization vectors. Ignored or reused initialization vectors (an arbitrary number required in conjunction with a secret key to encrypt data) increase the likelihood of information leaks.

  • Injection (SQLi)

    Injection (SQLi) and cross-site scripting (XSS) are two of the most common types of injection attacks. Here’s how it works:

    An attacker enters malicious code into the target program. An interpreter processes the code as part of the command or query, thereby altering the program’s execution. Thus, the attacker uses an SQL statement to interfere with the preexisting parameters that control the exchange of data between a web application and its database, thereby gaining administrative access.

  • Insecure Design

    This points to vulnerabilities that arise in software due to the lack of security implementations during its development. For instance, the lack of input validation can make way for injection attacks. Implementing security in the software development life cycle can be a challenge as it demands an entirely different perspective – threat modeling.

    Pro Tip: You can discover such vulnerabilities through vulnerability scanning; however, remediating them in a production site is more challenging than preventing them during the SDLC.

  • Security Misconfiguration

    For instance, if a developer writes flexible firewall rules and creates network shares for convenience during the development phase, but does not restore the original settings. Similarly, an administrator may authorize configuration changes for troubleshooting or some other purpose, then forget to reset them.

    Pro Tip: Establish a rigorous schedule and set automatic triggers to regularly review your security posture through frequent vulnerability scans and penetration tests.

Implementation

How to Perform a Vulnerability Scan?

Performing a vulnerability scan isn’t just about hitting “start” on a tool. It requires the right scope, timing, and strategy to get meaningful results. From asset discovery to remediation, here’s how to do it effectively:

Vulnerability Scanning Process Flowchart

Step 1: Identification and Preparation

  • Asset discovery: Continuously map infrastructure, including shadow IT, to gather foundational information.
  • Risk-based prioritization: Focus on assets that handle sensitive data or are critical to operations, and obtain necessary authorizations.
  • Tool selection: Choose scanners that align with the business environment, such as cloud-native or DevOps-integrated solutions.

Additionally, a baseline of the system’s current security posture should be established to compare against the scan results and create a historical database of vulnerabilities.

Step 2: Initiate The Vulnerability Scan

A vulnerability scanner then analyzes system configurations, software versions, and network exposure against a database of known threats to identify potential risks. The duration of such a scan can range from 10 minutes to 48 hours, depending on the scope, target complexity, and depth of analysis.

Initiate Vulnerability Scan

Step 3: Analysis

Not every vulnerability poses a real-world risk—your team must prioritize findings based on exploitability, business impact, and active threats. Even low-severity issues, when clustered in a high-value area, can be chained together to create a high-impact risk.

Similarly, if a medium-severity vulnerability is buried deep within an internal system with no known attack vector, it is considered low-risk. Thus, practical analysis is necessary to separate critical security gaps from low-risk noise.

Analysis of Vulnerabilities

Step 4: Reporting

Draft a vulnerability report that includes scan results, categorizes risks, and maps them to business-critical assets. Such a report acts as a blueprint for next steps and typically includes:

  • An executive summary that offers a high-level overview of key risks and business impact.
  • A technical breakdown of detailed findings, affected assets, risk scores, and proof-of-concept exploits.
  • Detailed remediation guidelines with actionable steps for fixing vulnerabilities tailored for security and development teams.
  • Augmented compliance mapping, aligning CVEs with security standards like OWASP, ISO, or SOC 2.

The depth of such reports also varies, based on stakeholders, namely development teams, which require a more in-depth insight, and executive/management teams, that require just a bird’s eye view.

Step 5: Remediation and Follow-up

Lastly, patch vulnerable systems, update outdated software, tighten misconfigurations, and apply secure coding practices to ensure that fixes don’t open up new attack surfaces.

Remediation Follow-up

Pro Tip: To sustain long-term security, embed vulnerability management into CI/CD pipelines. continuous scanning, contextual triage, and automated remediation workflows help catch issues early, reduce security debt, and maintain a clean, resilient codebase over time.

How Frequently Should You Run Vulnerability Scans?

Vulnerability scans should run bi-weekly or at least once a month, but with evolving threats, automation is key. Running scans 4-5 times a week ensures real-time detection, reducing exposure windows.

Pair automated scans with regressive testing for product and feature releases to avoid any security flaws slipping through the cracks without disrupting workflow.

Tools and Solutions

How to Choose the Right Vulnerability Scanning Tool for Your Stack

With AI-augmented scanning becoming table stakes, the real differentiator isn’t who scans—but how well, how deep, and how actionable those scans are. Here’s what seasoned CTOs should look for beyond the marketing gloss while choosing the right vulnerability scanning tool:

1. Coverage That Goes Beyond Checklists

  • Choose a tool that doesn’t just detect OWASP Top 10 but adapts to zero-days, business logic flaws, and evolving attack surfaces. Breadth is easy; depth is rare.

2. Compliance-Ready Insights, Not Just Reports

  • The right tool goes beyond mapping CVEs—it aligns findings with specific compliance mandates and simulates audit-readiness. Look for templated tests and gap-aware scoring.

3. Pentest-Grade Depth Without the Lag

  • Your scanner should simulate real adversaries, not just scan ports. Expect techniques like fuzzing, chained exploit testing, and protocol-aware analysis to surface deep flaws.

4. Risk-Driven Prioritization, Not Just Noise Filters

  • Volume is the enemy. Great scanners distill thousands of issues into a handful that matter, using contextual risk scoring and exploit intelligence to guide triage.

5. Built for CI/CD, Not Just Security Teams

  • Integration shouldn’t be a post-sale problem. Look for tools that plug into your CI/CD, ticketing, and alerting systems out of the box—and automate intelligently.

6. Accuracy That Cuts Through the Fog

  • False positives erode trust fast. A precision-focused scanner uses validation layers, behavioral context, and customizable rules to ensure alerts are worth acting on.

What are the Best Vulnerability Scanning Tools?

Not all vulnerability scanners are built the same. The right tool depends on your environment, scale, and security goals. Here’s a look at some of the top options and what makes them stand out:

1. Astra Vulnerability Scanner

Key Features:

  • Scanner Capabilities: Web Applications and APIs
  • Accuracy: Zero False Positives Assured (Vetted Scans)
  • Compliance: PCI-DSS, GDPR, HIPAA, SOC2, and ISO 27001
  • Integrations: Slack, Jira, GitHub, GitLab
  • Expert Remediation: Yes
  • Deployment: SaaS
  • Pricing: Starts at $69/month
  • Rating on G2: 4.6 out of 5

With 10,000+ tests tailored to detect OWASP, NIST, and SANS25 vulnerabilities, Astra’s automated scanner goes beyond conventional checks to identify emerging and existing vulnerabilities across web applications and their connected APIs.

Our expert-vetted scans ensure that every flagged issue is accurate and actionable. Hacker-style techniques, such as port scanning, scan-behind-logins, and subdomain takeover, simulate real-world attack scenarios, offering an offensive and strategic perspective.

More importantly, with easy tech stack integrations, industry-specific AI test cases, tailored reports, and a dedicated Astranaut Bot, we simplify cybersecurity for hundreds of businesses worldwide.

Pros:

  • Integrates seamlessly with Slack, Jira, GitHub, GitLab, and Jenkins
  • Unlimited automated scans for existing and emerging CVEs
  • Automated rescans to verify patches
  • CXO-friendly dashboard with custom reports for management and developers, respectively
  • Scans behind login screens

Limitations:

  • Only a 1-week $7 trial is available.

2. Intruder

    Key Features:

  • Scanner Capabilities: Websites, servers, and cloud
  • Accuracy: False positives present
  • Compliance: SOC2, PCI DSS, HIPAA, and ISO 27001
  • Integrations: GitHub, JIRA, Azure DevOps, and more
  • Expert Remediation: Yes
  • Deployment: SaaS
  • Pricing: Starts at $1958/year
  • Rating on G2: 4.8 out of 5

As a user-friendly cloud-first vulnerability scanner, Intruder offers innovative analysis with transparent, evidence-based reporting. Designed to support scaling digital infrastructures and the complexity that accompanies them, its focus on automation makes it a perfect fit for growing businesses.

With AI-powered scans, it targets known CVEs and zero-days alike to deliver a holistic view of your security posture.

Pros:

  • Simplified deployment and management of alerts.
  • Scans for 65000+ vulnerabilities

Limitations:

  • Can have false positives

3. Qualys

    Key Features:

  • Scanner Capabilities: Cloud and web applications
  • Accuracy: False positives possible
  • Compliance: PCI-DSS
  • Integrations: Cisco, IBM, Splunk
  • Expert Remediation: Yes
  • Deployment: SaaS or private cloud-based option
  • Pricing: Quote upon request
  • Rating on G2: 4.4 out of 5

Qualys brings enterprise-grade scanning across web apps, cloud assets, and endpoints with a continuously updated database of 20,000+ vulnerabilities. Its strength lies in breadth, particularly around compliance and asset inventory.

The platform offers a hybrid of automated scanning and customizable policies, producing rich, structured reports ideal for large security teams. However, its interface and remediation workflows can feel rigid for modern DevSecOps pipelines, and the learning curve is steeper than newer tools.

Pros:

  • Offers scan behind logins
  • Good fit for businesses with scaling infrastructure

Limitations:

  • Pricing can be a bit expensive for SMBs
  • Can have a steep learning curve.

Advanced Topics

Vulnerability Scanning Challenges & Best Practices

Vulnerability scanning can surface a flood of data—but not all of it is useful or easy to act on. To get real value, you need to navigate common challenges with the right best practices. Here’s what to watch for and how to stay effective:

1. Only Identifies Known Vulnerabilities

Most scanners operate on what they already know. If a threat isn’t in the database, it doesn’t exist—at least to the scanner which essentially leads to a slew of undetected zero-days and rapid exploits.

Best Practice: Choose a vulnerability scanner that integrates real-time threat intelligence and continuously updates its database to detect zero-day vulnerabilities.

2. Reports Point-in-Time Vulnerabilities

Vulnerability scans offer a snapshot of your security posture at a particular point in time, i.e., any new vulnerabilities that emerge between two scans are invisible. This creates blind spots, especially in fast-moving environments, where new code deployments, configuration changes, or third-party updates can introduce risks between scan intervals.

Best Practice: Implement continuous scanning and monitoring rather than relying on periodic scans. This ensures that new vulnerabilities are identified and addressed in real-time.

3. Unauthenticated Scans Lack Depth

Some scanning solutions might only offer unauthenticated scans with undetected internal vulnerabilities. Look for a scanner that can perform authenticated scans and scan behind login pages with the appropriate credentials through automated integration.

Best Practice: Use a scanner that supports authenticated scanning with credential-based access to test deeper application layers, including user roles and business logic vulnerabilities.

4. Surface-Level Tests

Vulnerability scans are an excellent cybersecurity solution for regular cyber-health checkups and continuous monitoring, however, for long-term cybersecurity and compliance, penetration tests are much more adept at finding vulnerabilities through thorough scanning and exploitation.

Best Practice: Pair vulnerability scanning with penetration testing to simulate real attacks and uncover deeper security risks that scanners might overlook.

5. Remediation Needs Manual Support

Vulnerability scans in themselves are an automated process. However, once completed, the remediation of vulnerabilities based on the report produced might require the aid of a security expert.

Best Practice: Integrate vulnerability management into CI/CD pipelines for automated remediation workflows, reducing security bottlenecks and consistently applying fixes.

Vulnerability Scanning Policy & its Importance

A vulnerability scanning policy defines what to scan, how often, and why certain systems take priority. In fast-moving stacks, it maintains consistency in efforts and relevance in outcomes. A clear policy brings structure, focus, and intent to your scanning program. It’s how security keeps pace with the business, not behind it. Most importantly, it ensures that your scanning program evolves in tandem with your infrastructure, not behind it.

Can Vulnerability Scans be Automated?

Yes, but automation isn’t just about speed—it’s about embedding security into the rhythm of development. By integrating scanners into your CI/CD pipeline, you shift detection left without slowing teams down. It’s how modern orgs move fast and build securely. Automation, done right, makes security invisible until it needs to be seen.

Industry Context

Vulnerability Scanning vs. Penetration Testing

Vulnerability scanning identifies potential security weaknesses in a system, while penetration testing simulates real-world attacks to exploit those vulnerabilities and assess their impact.

Penetration Testing Vulnerability Assessment
Penetration testing involves exploiting vulnerabilities to draw insights about them. Vulnerability assessment is focused on detecting and categorizing vulnerabilities in a system.
Penetration testing requires manual intervention on top of automated scanning. It is a mostly automated process involving vulnerability scanning tools.
Manual penetration testers can ensure zero false positives. It is almost impossible to achieve zero false positives with an automated vulnerability scanning .
Thanks to the human element of penetration testing, it detects business logic errors that remain undetected in a vulnerability scan. Vulnerability assessment often misses critical and complex vulnerabilities.
Penetration testing is a consuming and expensive procedure and for good reason. Automated vulnerability assessment takes significantly less time and money than pen testing.

Final Thoughts

Vulnerability scanning is an automated tool-based procedure. Hence, choosing the right tool cannot be emphasized enough. Using a tool that combines network, host, cloud, and API vulnerability scans strengthens the organization’s security posture.

Transforming your DevOps into DevSecOps is made much more convenient with vulnerability scanners like Astra. It is far easier and less expensive to find and deal with vulnerabilities during the software development life cycle before they pose a real threat.

Finding a pentesting company that conducts a static analysis of code and a dynamic analysis of the application in production will help you cover all your bases. Complemented by other security measures like pentesting, regular scans are necessary to create a layered defense approach.

Why Astra DAST Vulnerability Scanner?

Astra’s vulnerability scanner conducts 13,000+ tests to detect a wide range of vulnerabilities, including those listed by OWASP Top 10, SANS 25, and NIST.

At Astra, we prioritize user-friendly security. Take, for instance, our login recorder extension, which allows the automated scanner to scan behind login pages without requiring the site owners to authorize it repeatedly.

Your vulnerability scanning experience with Astra is convenient through an interactive dashboard where you can visualize the vulnerability analysis and remediation status. Our security experts also promise zero false positives in our vetted scans.

The pentest compliance feature we launched also shows you what compliance regulations you meet or fail to meet based on the state of vulnerabilities found in your system during the scan.

You can also integrate platforms like GitHub, Jira, and Slack to make your remediation planning independent from the dashboard.

FAQs

What do you mean by vulnerability scanning?

Vulnerability scanning is the process of an automated tool scanning an organisation’s IT networks, applications, devices, and other internal or external assets for known potential security loopholes and vulnerabilities.

At the end of every vulnerability scan, you receive a report that documents the vulnerabilities found, along with risk scores for each vulnerability and, in some cases, security recommendations.

What are the types of vulnerability scanners?

The types of vulnerability scanners are:

Network vulnerability scanners: Find vulnerabilities in network infrastructure. 
Host-based vulnerability scanners: Assess individual systems for vulnerabilities. 
Cloud vulnerability scanners: Find vulnerabilities in cloud environments.
API vulnerability scanners: Detect vulnerabilities in application programming interfaces.

Why is vulnerability scanning important?

Vulnerability scanning helps you prevent data breaches by protecting systems, applications, and networks from cyberattacks and remediating vulnerabilities before they can be exploited. It also helps you achieve compliance and build trust.