Exploring Web Vulnerability Scanners: Enhancing Web Application Security

In day-to-day life, Web vulnerabilities are becoming more prevalent. Therefore, it's crucial to identify and address these security risks, ensuring compliance and maintaining a strong cybersecurity stance in today's digital environment. Security professionals commonly rely on a variety of vulnerability scanning tools for these tasks.

Vulnerability scanners are automated tools designed to scan applications and detect known vulnerability signatures.

Hello everyone! In today's article, we will explore various web vulnerability scanner tools and learn how to conduct vulnerability scanning.

Kali Linux includes a variety of built-in vulnerability scanning tools, which can be accessed through the Web Applications menu under Web Vulnerability Scanners.

Some of these pre-installed tools include Cadaver, davtest, Nikto, Skipfish, Wapiti, whatweb, and Wpscan. 

Similarly, Parrot Security OS also provides a selection of pre-installed vulnerability scanning tools.

Penetration testers often employ two or three different comprehensive scanners simultaneously on the same target to ensure accurate results. It's important to note that some vulnerability scanners also incorporate attack capabilities.

Vulnerability scanners can be quite "noisy" and are often detectable by the target system. However, these scans are frequently overlooked as they are part of routine background probing across the Internet. In some cases, attackers conduct large-scale scans against a target to mask their true attack intentions or to prompt defenders to disable detection systems due to the high volume of alerts they generate.

Let's explore a quick survey of important vulnerability scanners, available on Kali Linux:

• Cadaver: Cadaver serves as a command-line WebDAV client tailored for Unix-like systems. It enables users to interact with WebDAV servers by uploading, downloading, and manipulating resources. Although not primarily a vulnerability scanner, it can aid in exploring and assessing WebDAV implementations for potential security issues.
• Davtest: Davtest is a specialized tool crafted for security testing on WebDAV-enabled servers. It is designed to identify common misconfigurations and vulnerabilities within WebDAV setups, facilitating the detection and mitigation of security risks.
• Nikto: Nikto is a Perl-based open-source scanner featuring IDS evasion techniques and customizable modules. However, it is considered somewhat outdated compared to newer scanning tools.
• Skipfish: Skipfish generates interactive sitemaps with vulnerability annotations through recursive and dictionary-based crawls. It is particularly useful for comprehensive web application security assessments.
• Wapiti: Wapiti is a Python-based open-source vulnerability scanner tailored for web applications. It aids in the discovery of potential security weaknesses and vulnerabilities within web services.
• WhatWeb: WhatWeb operates as a reconnaissance tool identifying the web technologies utilized by a website. It scrutinizes HTTP headers, HTML content, and related parameters to ascertain the underlying software stack supporting the website.
• WPScan: WPScan is a black box WordPress vulnerability scanner. It specializes in enumerating WordPress installations, plugins, and themes, subsequently conducting scans to identify known vulnerabilities associated with them.

                         

These tools, readily available on Kali Linux, offer a diverse range of capabilities for vulnerability scanning and security testing, catering to various aspects of web application security and system assessments.

There are several other tools available that are not included by default in Kali Linux and Parrot Security OS. Some of these tools may be outdated and less useful in recent times, but I will provide a brief explanation of each:

• Arachnid: An open-source Ruby framework designed for response validation and reducing false positives during security assessments.
• GoLismero: GoLismero is a tool that maps web applications and detects common vulnerabilities, saving results in various formats for further analysis and remediation.
• Vega: Vega is a GUI-based, cross-platform (Java) open-source vulnerability scanner offering extensive user customization options for comprehensive security assessments.
• w3af (acquired by Rapid7): w3af is a comprehensive Python testing platform featuring both a graphical user interface (GUI) and a command-line interface (CLI). It conducts vulnerability scans after mapping the target website and may integrate with the Metasploit Framework in the future.
• Webscarab (OWASP): Webscarab is a Java framework primarily used for analyzing HTTP/HTTPS protocols. It functions as an intercepting proxy, fuzzer, and basic scanner, aiding in security testing and protocol analysis.
• Webshag: Webshag is a Python-based website crawler and scanner equipped with advanced IDS (Intrusion Detection System) evasion capabilities, useful for identifying vulnerabilities in web applications.
• Websploit: Websploit is a framework designed for conducting wired and wireless network attacks. While not strictly a vulnerability scanner, it offers tools for various network security assessments and penetration testing scenarios.

These tools, although not pre-installed on Kali Linux or Parrot Security OS, can still be valuable additions to a security professional's toolkit depending on specific testing needs and use cases. However, users should exercise caution with older tools and consider newer alternatives for more up-to-date security assessments.

Most testers typically initiate website testing with Nikto, a straightforward scanner known for its reporting capabilities, although it tends to deliver limited but accurate results. Here's a sample output from a Nikto scan:

Nikto Scan report

The subsequent step involves utilizing advanced scanners capable of detecting a larger array of vulnerabilities, albeit these scanners often require significantly more time to complete their scans. It's not uncommon for complex vulnerability assessments, determined by factors like the number of pages to be scanned and the site's intricacy (including pages with user input features like search functions or data-gathering forms for backend databases), to extend over several days.

One of the most effective scanners known for discovering verified vulnerabilities is Subgraph's Vega. Vega scans the target and categorizes vulnerabilities into high, medium, low, or informational severity levels. Testers can drill down into specific findings by clicking on identified results. Additionally, testers can customize the Java-based search modules to focus on specific vulnerabilities or uncover new ones.

Subgraph's vega

Another highly recommended scanner is Skipfish, an open-source web application security tool that provides preconfigured vulnerability scans in line with industry security standards. Skipfish is noted for its efficiency in swiftly assessing a target. However, during extended testing sessions, it may encounter intermittent failures. Therefore, effectively utilizing Skipfish requires a thorough understanding of its capabilities and limitations across various testing scenarios.

Skipfish

In my upcoming article, I will explore each of these tools in detail, focusing on their usefulness and installation process. Stay tuned to learn more!