Vulnerability scanning is the automated process of searching for security weaknesses in computer systems or software. The objective is to identify potential points of exploitation by malicious actors. When used by professionals, vulnerability scanning tools can become a crucial part of any IT security strategy. There are many different scanners available and here we cast our eye over some of the options.

Vulnerability scanning

This important weapon in a cyber security professional’s arsenal identifies security flaws within systems, networks and software applications. It involves the use of specialised tools or software, and essentially sees the scanner seeking known vulnerabilities, misconfigurations or potential entry points. Deploying vulnerability scanning is a proactive measure, enabling organisations to assess security gaps before they can be exploited by cyber-criminals.

Typically, the findings of a scan can include the following:

  • Outdated software or operating systems
  • Misconfigured security settings
  • Known software vulnerabilities (missing patches)
  • Open ports and services that could be potential entry points
  • Default or weak passwords
  • Unencrypted sensitive data
  • Missing security updates or patches
  • Presence of malware or malicious code
  • Lack of proper access controls
  • Insecure network configurations

How does a vulnerability scanning tool work?

Typically, they systematically examine a target system, network or software application using the following process:

  • Discovery
  • Enumeration
  • Vulnerability identification
  • Assessment
  • Reporting
  • Continuous monitoring
  • Integration

Discovery: The tool scans the target environment to identify active devices, hosts and services. This could involve techniques such as network discovery or port scanning to identify open ports and running services.

Enumeration: Detailed information about the identified services is gathered, such as software versions, configurations and protocols in use. This information helps in identifying known vulnerabilities associated with specific software versions.

Vulnerability identification: The gathered information is then compared against a database of known vulnerabilities. This usually includes information about security flaws, weaknesses and misconfigurations in various software and systems.

Assessment: The tool assesses the severity and potential impact of identified vulnerabilities. It may then assign risk scores or ratings to help prioritise remediation efforts.

Reporting: Comprehensive reports are then generated listing and describing the identified vulnerabilities. Additional information presented includes the potential impact of each vulnerability and recommended actions for remediation.

Continuous Monitoring: Many vulnerability scanning tools support ongoing or periodic scans to make sure that new vulnerabilities are detected as they emerge. Monitoring also helps to ensure that previously identified issues have been resolved.

Integration: Vulnerability scanning tools typically integrate with other security tools and systems. These include intrusion detection systems (IDS), security information and event management (SIEM) systems, plus patch management solutions. This integration helps to enhance an organisation’s overall security posture.

Active & Passive techniques

It is important to note that vulnerability scanning tools use a combination of active and passive techniques. Active scanning involves directly interacting with the target to gather information and assess vulnerabilities. Passive scanning observes network traffic and activities without direct interaction. Vulnerability scanning tools are invaluable when it comes to identifying and prioritising security issues. As aforementioned, there are lots of tools that you can use and below are some options to consider (listed alphabetically).

Vulnerability scan tools

Acunetix Ltd: A web vulnerability scanner with advanced crawling technology; users can find vulnerabilities on web pages that are password protected.

Burp Suite: This web scanner is frequently updated and can integrate with bug tracking systems such as Jira; this means that users can generate simple tickets.

Nessus: This is a very popular vulnerability scanner and has over two million downloads around the world at the time of writing.

Nexpose Community: This robust scanning solution collects real-time data, allowing organisations to view their networks on a live basis.

Nmap: This is an open source, FOC security scanner used by many organisations for network discovery, monitoring host or service uptime and more.

OpenVAS: Another open source solution, this is maintained by Greenbone Networks and has a regularly updated community feed with over 50,000 vulnerability tests.

Qualys: Their Qualys Cloud Platform has a robust vulnerability scanner which helps organisations to centralise their vulnerability management. The Qualys Web Application Scanner is another solution worth looking at; this cloud-based application finds official and unofficial apps throughout an environment.

Tenable, Inc.: Teneble.sc and Teneble.io provide network and web vulnerability assessments using Nessus technology. They create a detailed risk score via the use of ‘Predictive Prioritisation’ to combine vulnerability data, threat intelligence and data science.

Tripwire: The Tripwire IP360 scanner is scalable and can scan everything in an organisation’s environment. This includes previously-undetected assets using both agent-based and agentless scans.

In conclusion

There are many more vulnerability scanning tools to choose from than those listed above, including:

  • Aircrack-ng
  • Detectify AB
  • Invicti
  • ManageEngine
  • Metasploit
  • Microsoft Baseline Security Analyzer
  • Netsparker
  • Nikto
  • OWASP ZAP
  • Probely
  • Rapid7
  • SolarWinds
  • Sqlmap
  • Wireshark
  • W3af

As with anything in life, finding the right tool / tools for you is essential. Each has its own strengths and weaknesses, which may or may not compliment your own abilities. Of course, it is vital for any organisation contemplating vulnerability scans to ensure they are completed by professionals. You can have the best scanning tool in the world at your disposal but they must have an expert at the helm to generate successful results.

It is also worth noting that vulnerability scans can be enhanced through the use of penetration testing. Whilst the scans can uncover thousands of vulnerabilities, they do not account for an organisation’s overall security set up. Pen tests can uncover exactly which vulnerabilities may allow access to your environment. For more information on these, contact our cyber security professionals.