Top 20 Interview Questions and Answers of OpenVAS and Metasploit

Introduction

OpenVAS and Metasploit are essential tools in penetration testing. OpenVAS is an open-source tool that scans networks for vulnerabilities, providing detailed reports on security weaknesses. It helps organizations identify and fix potential security issues before attackers can exploit them. 

Metasploit, on the other hand, is a framework that allows security professionals to exploit system vulnerabilities to test their defenses. It includes a vast library of exploits and payloads for simulating real-world attacks. Understanding and using these tools effectively can demonstrate your technical skills and practical knowledge in an interview, showcasing your ability to enhance an organization's security posture.

Q1: What Is OpenVAS?

A: OpenVAS is an abbreviation for Open Vulnerability Assessment System. It is not just a tool but a complete framework consisting of several services and tools, offering a comprehensive and robust vulnerability scanning and management solution, Like an antivirus solution with signatures to detect known malware.

OpenVAS has a set of network vulnerability tests (NVTs). The NVTs are conducted using plugins developed using Nessus Attack Scripting Language (NASL) code. There are more than 50,000 NVTs in OpenVAS, and new NVTs are added regularly.

Q2: What Are The Different Scan Profiles In OpenVAS?

A: OpenVAS has several predefined scan profiles. Depending on the specific requirement, you can choose one of the following scan profiles:

• Discovery

• Full and Fast

• Full and Fast Ultimate

• Full and Very Deep

• Full and Very Deep Ultimate

• Host Discovery

• System Discovery

Q3: What Is CVSS Calculator?

A: The Common Vulnerability Scoring System (CVSS) is the baseline many security products use to calculate a vulnerability's severity. CVSS takes into consideration multiple parameters before computing the vulnerability score. OpenVAS offers a ready-to-use CVSS calculator that you can use to calculate vulnerability scores. You can access the CVSS calculator at Extras ➤ CVSS Calculator,

Q4: What Are The Different Reporting Formats Offered By OpenVAS?

A: A comprehensive report is critical because it will help administrators fix the identified vulnerabilities. OpenVAS supports multiple report formats, listed here:

• Anonymous XML

• ARF

• CPE

• CSV Hosts

• CSV Results

• HTML

• ITG

• LaTeX

• NBE

• PDF

• Topology SVG

• TXT

• Verinice ISM

• Verinice ITG

• XML

Q5: Give A Brief About Metasploit

A: Metasploit is not just a single tool. It is a complete framework. It is extremely robust and flexible and has many tools to perform various simple and complex tasks. It has a unique ability to perform almost all the penetration testing life cycle tasks. By using Metasploit, you don't need to reinvent the wheel; you just focus on the penetration testingobjectives and all the supporting actions can be performed using various framework components.

Q6: What Are The Three Editions Of Metasploit?

A: While Metasploit is powerful and capable, you must clearly understand its structure and components to use it efficiently. There are three editions of Metasploit.

• Metasploit Pro

• Metasploit Community

• Metasploit Framework

Q7: What Are Auxiliaries?

A: Auxiliaries are the modules that make Metasploit so flexible. A Metasploit auxiliary is a piece of code specifically written to perform a task. For example, you may want to check whether a particular FTP server allows anonymous access or if your web server is vulnerable to a heartbleed attack. An auxiliary module exists for all these tasks.

Q8: Explain Payload

A: exploit is the code that will be used against the vulnerable component. The exploit code may run successfully, but the payload defines what you want to happen once the exploit is successful. In simple terms, a payload is the action that needs to be performed after the execution of an exploit. For example, if you want to create a reverse shell back to your system, then you need to select the appropriate Metasploit payload for that. Metasploit has about 42 payloads in Singles, Stagers, and Stages.

Q9: What Are Exploits In Metasploit?

A: Exploits are an extremely important part of Metasploit. The whole purpose of the framework is to offer exploits for various vulnerabilities. An exploit is an actual code that will execute on the target system to exploit the vulnerability. Metasploit has more than 1,800 exploits in 17 categories. The following are the various categories of exploits available in Metasploit:

Aix, Android, Apple_ios, Bsdi, Dialup, Firefox, Freebsd, HP-UX, Irix, Linux, Mainframe, Multi, and more.

Q10: How Can You Manage Payloads Without Them Getting Detected By Antivirus Software?

A: Metasploit helps you generate various payloads you can send to the target in multiple ways. In the process, your payload may get detected by antivirus software or any security software on the target system. This is where encoders can be of help. Encoders use various techniques and algorithms to obfuscate the payload to prevent it from being detected by antivirus software. Metasploit has about 40 encoders in ten categories: Cmd, Generic, Mipsbe, Mipsle, Php, Ppc, Ruby, Sparc, X64, and X86.

Q11: What Are Some Post-Exploitation Activities That Post Modules Can Help With?

A: Once you have gained basic access to your target system using any available exploits, you can use the post modules to further infiltrate the target system. These modules help you in all the post-exploitation activities, including the following:

• Escalating user privileges to root or administrator

• Retrieving the system credentials

• Stealing cookies and saved credentials

• Capturing keystrokes on the target system

• Executing custom PowerShell scripts for performing additional tasks

• Making access persistent

Q12: What Are The Two Variables Of Metasploit?

A: Metasploit has some variables that need to be set before you execute any module or exploit. These variables are of two types.

• Local: Local variables are limited and valid only for a single instance.

• Global: Global variables, once defined, are applicable across the framework and can be reused wherever required.

Q13: How Does OpenVAS Differ From Other Vulnerability Scanners?

A: OpenVAS differs from other vulnerability scanners in several key ways:

• Open Source: Unlike many commercial scanners, OpenVAS is open source, making it accessible to a wider range of users and allowing for community contributions and enhancements.

• Comprehensive PluginPlugin Coverage: OpenVAS has a large library of regularly updated Network Vulnerability Tests (NVTs) that provide extensive coverage of known vulnerabilities.

• Cost: Being open source, OpenVAS can be a cost-effective solution for organizations with limited budgets compared to expensive commercial alternatives.

• Flexibility: Users can customize and extend OpenVAS to meet specific needs, which can be more restrictive with proprietary solutions.

• Integration with GVM: OpenVAS is part of the Greenbone Vulnerability Management (GVM) framework, which provides a holistic approach to vulnerability management with additional tools and features.

Q14: Can You Explain The Typical Workflow Of A Vulnerability Scan Using OpenVAS?

A: The typical workflow of a vulnerability scan using OpenVAS involves several steps:

• Installation and Setup: Install OpenVAS and perform the initial configuration. This includes setting up the Greenbone Security Assistant (GSA) web interface and downloading the latest NVTs.

• Target Definition: Define the target systems that you want to scan. This can be a single IP, a range of IPs, or an entire network.

• Scan Configuration: Select or customize a scan configuration. OpenVAS provides several predefined scan configurations (e.g., full and fast scan, host discovery scan) that can be used or modified based on specific needs.

• Running the Scan: Initiate the scan through the GSA interface. OpenVAS will then perform the vulnerability assessment by testing the target systems against its database of NVTs.

• Analyzing Results: Once the scan is complete, analyze the results via the GSA. The results will include detailed information about discovered vulnerabilities, their severity, and potential remediation steps.

• Reporting: Generate and export reports in the desired format for documentation, compliance, or further analysis.

Q15: How Can OpenVAS Be Integrated Into An Organization's Security Infrastructure?

A: OpenVAS can be integrated into an organization's existing security infrastructure in several ways:

• SIEM Integration: OpenVAS can be integrated with Security Information and Event Management (SIEM) systems to correlate vulnerability data with other security events and provide a comprehensive view of the organization's security posture.

• Automation: Through scripting and APIs, OpenVAS can be integrated into automated workflows, allowing for regular and scheduled scans, automated report generation, and even automated remediation processes in conjunction with other security tools.

• Centralized Management: When deployed with the Greenbone Security Manager (GSM), multiple OpenVAS instances can be centrally managed, making it easier to scale and manage large environments.

• Integration with Patch Management Systems: OpenVAS can provide valuable vulnerability data to patch management systems, ensuring that identified vulnerabilities are prioritized and addressed in patching schedules.

• Custom Alerts: Configure OpenVAS to send alerts and notifications to security teams via email or other communication channels when critical vulnerabilities are detected, enabling quicker response and mitigation

Q16: How Does Metasploit Differ From Other Penetration Testing Tools?

A: Metasploit differs from other penetration testing tools in several key ways:

• Modularity: Metasploit's modular architecture allows for the easy addition of new exploits, payloads, and auxiliary modules, making it highly extensible.

• Community and Commercial Versions: While Metasploit Framework is open source and free, Metasploit Pro offers additional commercial features for enterprise use, such as automated exploitation, vulnerability validation, and phishing campaigns.

• Comprehensive Exploit Database: Metasploit's exploit database is one of the most extensive available, constantly updated by the community and Rapid7 developers.

• Integration: Metasploit integrates well with other security tools and frameworks, including Nmap for scanning and Nessus for vulnerability assessment, enhancing its effectiveness in a comprehensive security testing workflow.

• User-Friendly Interfaces: Metasploit provides both a command-line interface (msfconsole) and a graphical user interface (Armitage for the community version and Metasploit Pro's web interface), catering to both advanced users and those preferring a GUI.

Q17: Can You Explain The Typical Workflow Of Using Metasploit For A Penetration Test?

A: The typical workflow of using Metasploit for a penetration test involves several steps:

• Reconnaissance and Scanning: Use tools like Nmap to perform reconnaissance and identify potential targets and open services on the network.

• Selecting and Configuring Exploits: Based on the reconnaissance data, select an appropriate exploit from Metasploit's database. Configure the exploit parameters, such as the target IP address and port.

• Choosing Payloads: Select a payload that will be executed once the exploit is successful. Common payloads include Meterpreter shells, reverse TCP shells or command execution payloads.

• Launching the Exploit: Execute the exploit against the target. Metasploit will attempt to deliver the payload using the chosen exploit.

• Post-Exploitation: If the exploit is successful, use post-exploitation modules to perform further actions on the compromised system, such as gathering sensitive information, escalating privileges, or establishing persistence.

• Reporting: Document the findings and actions taken during the penetration test. If using Metasploit Pro, generate detailed reports to share with stakeholders for remediation planning.

Q18: How Can Metasploit Be Integrated Into An Organization's Security Infrastructure?

A: Metasploit can be integrated into an organization's existing security infrastructure in several ways:

• SIEM Integration: Metasploit can be integrated with Security Information and Event Management (SIEM) systems to correlate attack data with other security events, providing a comprehensive view of security incidents.

• Automation: Scripts and the Metasploit RPC API can be used to integrate it into automated security testing workflows, allowing for continuous integration and continuous deployment (CI/CD) pipeline testing.

• Vulnerability Management Systems: Metasploit can be used with vulnerability management systems like Nexpose or Nessus to validate identified vulnerabilities and ensure they are exploitable, prioritizing remediation efforts.

• Incident Response: Security teams can use Metasploit to simulate attacks and test incident response procedures, ensuring the organization is prepared for real-world attacks.

• Custom Development: Organizations can develop custom Metasploit modules to address specific needs or integrate with proprietary systems, enhancing the framework's capabilities tailored to the organization's environment.

Q19: What Is The Metasploit Meterpreter, And What Are Some Of Its Key Functionalities?

A: Meterpreter (short for Meta-Interpreter) is an advanced and highly extensible payload within the Metasploit framework. It provides an interactive shell that runs on the target machine, allowing penetration testers to execute commands and scripts post-exploitation. Some of its key functionalities include:

• In-Memory Execution: Meterpreter operates entirely in memory and does not write anything to disk, making it stealthier and harder for antivirus software to detect.

• Command Execution: Testers can execute system commands, run scripts, and upload or download files to and from the target machine.

• Privilege Escalation: Meterpreter includes modules to exploit local vulnerabilities for privilege escalation, allowing the tester to gain higher-level access to the compromised system.

• Network Pivoting: It can create a proxy connection to other systems on the network, enabling lateral movement and further exploitation of networked systems.

• Session Management: Meterpreter supports multiple concurrent sessions, allowing the tester to simultaneously manage and switch between multiple compromised machines.

• Interactive Control: This feature provides features like webcam control, keystroke logging, and screenshot capture, enhancing the scope of post-exploitation activities.

Q20: How Does Metasploit Handle The Concept Of Encoding, And Why Is It Important?

A: Metasploit handles encoding through the use of encoders, which are used to transform payloads to evade detection by intrusion detection systems (IDS), intrusion prevention systems (IPS), and antivirus software. Encoding is important for several reasons:

• Evasion: By encoding payloads, Metasploit can bypass signature-based detection mechanisms used by security solutions that look for known malicious code patterns.

• Obfuscation: Encoding helps obfuscate the payload, making it harder for defenders to analyze and understand the exploit and its intended impact.

• Compatibility: Some exploits require payloads to be in a specific format or to avoid certain characters (such as null bytes), and encoding can help achieve this compatibility.

• Multiple Encoders: Metasploit provides various encoders, such as shikata_ga_nai, x86/countdown, and cmd/echo, allowing testers to choose the most effective one for their needs.

• Iteration: Encoders can be applied multiple times in layers, adding complexity and making it even more challenging for security mechanisms to detect the payload.

Conclusion

JanBask Training's QA courses can help you gain practical skills in using OpenVAS and Metasploit effectively. In an interview, discussing how you've used these tools, enhanced by JanBask's hands-on training, can demonstrate your readiness to secure systems and handle real-world security challenges.