Networks are the backbone of modern-day businesses, and their security is critical to prevent unauthorised access, data breaches, and other security incidents. Network vulnerability scanning is a proactive approach to identifying security vulnerabilities before attackers can exploit them. This article will discuss network vulnerability scanning in detail, including its definition, types, benefits, and best practices.
Let’s get started!
What Is Network Vulnerability Scanning?
Network vulnerability scanning identifies security vulnerabilities in a network infrastructure or system using a network vulnerability scanner to reduce cyber exposure. It involves using specialised software tools to scan the network and identify potential vulnerabilities in various network components, including systems, devices, applications, and databases.
Network vulnerability scanners aim to identify security threats before attackers can exploit them, allowing businesses to take proactive measures to secure their network infrastructure. Network vulnerability scanning is essential to security management and is required for regulatory compliance in many industries.
How Does Network Vulnerability Scanning Work?
Network vulnerability scanning uses specialised software tools to scan a network infrastructure or system and identify potential vulnerabilities. The vulnerability scanning tools send probes or packets to the network, simulate an attacker’s actions, and analyse the responses to identify potential vulnerabilities.
a) Scanning Preparation
The scanning tool is configured with specific parameters, such as the range of IP addresses, the type of scanning to perform (active or passive), and the scanning frequency.
b) Discovery
The tool undertakes network scanning to identify devices, services, and applications. It gathers information about the network infrastructure, including the types of devices connected, the IP addresses assigned, and the operating systems used.
c) Enumeration
The scanning tool analyses the information gathered in the discovery phase to identify specific vulnerabilities. This involves probing devices and services to identify potential vulnerabilities, such as open ports, known vulnerabilities in software versions, weak passwords, and misconfigured systems.
d) Vulnerability Assessment
The scanning tool assigns a risk score to each vulnerability based on its severity, impact, and exploitability. This helps prioritise the remediation efforts and address the most critical vulnerabilities first.
e) Reporting
The scanning tool generates a report summarising the identified vulnerabilities, their risk level, and recommendations for remediation. The report helps IT security teams prioritise addressing the identified vulnerabilities and securing the network infrastructure.
f) Remediation
The IT security team addresses the identified vulnerabilities, such as installing patches, updating software versions, or reconfiguring systems, to improve the network infrastructure’s security posture.
Types of Network Vulnerability Scanning
There are two types of network vulnerability scanning: active and passive.
1. Active Scanning
Active scanning involves probing the network infrastructure or system to identify vulnerabilities. It includes sending packets to the network and analysing the responses to identify potential vulnerabilities. Active scanning is an effective method for identifying vulnerabilities in a network because it simulates a potential attacker’s actions. Also, active scanning tools can identify open ports, detect network services, and probe for weaknesses in applications, operating systems, and network devices.
2. Passive Scanning
On the other hand, passive scanning involves monitoring the network traffic to identify potential vulnerabilities without sending packets to the network. Passive scanning tools collect information about the network infrastructure by monitoring network traffic, such as IP addresses, protocols, and devices connected to the network.
Passive scanning is less intrusive than active scanning, and it can help identify potential vulnerabilities in devices or systems that may not respond to active scanning.
In addition to active and passive scanning, there are other specialised scanning techniques, such as:
3. Credentialed Scanning
This uses valid login credentials to access the network devices and applications, allowing the scanner to identify vulnerabilities that are not visible from the outside.
4. Unauthenticated Scanning
This type of active scanning does not require login credentials but can still identify vulnerabilities in the network infrastructure.
5. Authenticated Scanning
This type of active scanning requires valid login credentials to identify vulnerabilities. A more comprehensive scanning technique can identify the vulnerabilities of the operating system, applications, and network devices.
Network Vulnerability Scanning Tools
There are many network vulnerability scanning tools available in the market. Here are some of the common ones:
i. Nessus
Nessus is a widely used network vulnerability scanner that performs active and passive scans. Nessus scans a network and identifies potential vulnerabilities in the network devices, servers, and applications. It uses a database of known vulnerabilities to identify vulnerabilities in the scanned systems.
ii. OpenVAS
OpenVAS (Open Vulnerability Assessment System) is a popular open-source network vulnerability scanner allowing security professionals to scan networks for vulnerabilities. It can scan for vulnerabilities in various operating systems, applications, and network devices.
OpenVAS uses a database of known vulnerabilities and checks for these vulnerabilities by sending specific packets to the target system. It then generates a report that details any vulnerabilities found, along with severity ratings and recommends actions.
iii. Nmap
Nmap is an open-source network vulnerability scanner used to discover hosts and services on a computer network, thus creating a “map” of the network. It can perform various network exploration and security auditing tasks, such as identifying open ports, operating systems, and software versions running on networked devices.
Nmap can also detect vulnerabilities in networked systems by performing various types of scans, including port scans, version detection scans, and vulnerability scans. Vulnerability scans use a database of known vulnerabilities and exploit techniques to identify potential security weaknesses in the target systems.
iv. Nikto
Nikto is another open-source web server scanner that can identify web server and application vulnerabilities. It is designed to perform comprehensive tests against web servers for various known vulnerabilities, misconfigurations, and security weaknesses.
Nikto scans over 6700 potentially dangerous files or programs and over 1250 out-of-date server software versions. It can also check for misconfigured web server options, insecure configurations, and information leaks.
The tool is easy to use and free on multiple platforms, including Linux, Unix, Windows, and macOS. Nikto can also generate reports in various formats, including HTML, XML, CSV, and NBE, making sharing results with other team members easy.
v. OSSEC
OSSEC is an open-source host-based intrusion detection system that can monitor network devices and systems for signs of compromise. It can detect various attack types, including malware infections, brute-force attacks, and system configuration changes.
vi. Metasploit
Metasploit undertakes a network vulnerability test with a vulnerability scanning module. It can identify vulnerabilities in network devices, operating systems, and applications and provides detailed reports.
These are just a few of the many network vulnerability scanning tools available. Selecting a tool that can perform the required scanning types and generate reports that meet the organisation’s needs is essential. Additionally, it is important to ensure that the scanning tool is kept up-to-date with the latest vulnerability definitions to ensure accurate scanning results.
Features to Consider When Choosing a Vulnerability Scanning Tool
Choosing the right vulnerability scanning tool can be a challenging task, given the many options available in the market. Here are key features to consider when selecting one:
1. Scan Types
Vulnerability scanning tools can perform various types of scans, including:
- Authenticated and unauthenticated scans.
- Internal and external scans.
- Active and passive scans.
Consider the types of scans required for your organisation’s network infrastructure and choose a tool that can perform the required scans.
2. Vulnerability Database
Vulnerability scanning tools rely on a vulnerability database to identify network devices, operating systems, and application vulnerabilities. Consider the vulnerability database the scanning tool uses and ensure it is up-to-date with the latest flaws.
3. Reporting
Reporting is a crucial feature of vulnerability scanning tools. Consider the tool’s reporting capabilities, including the types of reports generated, the level of detail provided, and the format of the reports. Ensure that the reports meet your organisation’s needs for compliance, risk management, and communication with stakeholders.
4. Integration
Vulnerability scanning tools can integrate with other security tools, such as intrusion detection and prevention systems, firewalls, and security information and event management systems. Consider the integration capabilities of the tool and ensure that it can work seamlessly with your organisation’s existing security infrastructure.
5. Ease of Use
Vulnerability scanning tools can be complex to set up and use. Consider the tool’s ease of use, including the user interface, configuration, and customisation options. Ensure that your organisation’s security team can use the tool effectively without requiring extensive training or technical expertise.
6. Cost
Vulnerability scanning tools vary widely, depending on their features, functionality, and licensing models. Consider the cost of the tool, including any ongoing maintenance and support fees, and ensure that it fits within your organisation’s budget.
7. Technical Support
Vulnerability scanning tools can encounter technical issues requiring assistance from the developer. Consider the level of technical support the vendor provides, including the availability of support channels, response times, and expertise.
Choosing the right vulnerability scanning tool requires careful consideration of the tool’s features, functionality, cost, and the organisation’s specific needs and technical expertise. Businesses can proactively manage security risks and protect their network infrastructure from potential vulnerabilities by evaluating these factors and selecting a tool that meets the organisation’s requirements.
Frequently Asked Questions on Network Vulnerability Scanning
a) What is vulnerability management?
Vulnerability management is a security process that involves identifying, evaluating, prioritising, and mitigating security vulnerabilities in a network infrastructure or system. Vulnerability management aims to proactively address potential security risks before attackers can exploit them, thereby reducing the likelihood and impact of a security breach.
b) What is a hosted scan?
A hosted scan refers to a network vulnerability scan where a third-party service provider hosts the scanning tool and conducts the scan on behalf of the client. The scanning tool is typically a software application that scans the client’s website, network, or application for vulnerabilities or potential security threats.
c) What are the main types of vulnerability?
There are many types of vulnerabilities, but here are some common ones:
Software vulnerabilities: These are weaknesses in software that attackers can exploit to gain unauthorised access, execute arbitrary code, or cause a denial of service. Network vulnerabilities are weaknesses in network infrastructure or protocols that attackers can exploit to gain unauthorised access or perform attacks like man-in-the-middle or denial of service.
Physical vulnerabilities are weaknesses in physical security measures such as locks, cameras, or access control systems that attackers can exploit to gain physical access to sensitive areas or equipment. We also have Configuration vulnerabilities. These are weaknesses in configuring software, systems, or networks that attackers can exploit to gain unauthorised access or perform attacks like privilege escalation.
Featured Image Source: unsplash.com
