In today’s digital landscape, securing your organization’s external network is more critical than ever. As a leading penetration testing company, we’ve witnessed countless instances where organizations fall victim to cyber attacks due to overlooked fundamental security measures.
In this comprehensive guide, we’ll share our expertise and provide you with practical recommendations to enhance your external network’s security posture.
We’ll cover essential topics such as:
- minimizing your attack surface
- implementing effective software update management
- establishing a comprehensive password policy
- applying system hardening techniques
- implementing a robust vulnerability management process
- conducting regular penetration testing
By following these simple steps, you can significantly reduce the risk of breaches and protect your valuable assets.
1. Minimize Your Attack Surface
The first step in securing your external network is to minimize your attack surface by reducing the number of publicly accessible services within your IT infrastructure’s perimeter.
Every service exposed to the public internet presents a potential entry point for malicious actors.
To mitigate this risk, it’s essential to limit public access to only those services that are absolutely necessary for your business operations.
Restrict access to auxiliary services and administrative interfaces by making them available only to a limited range of IP addresses or requiring users to connect via a VPN. While this may require extra effort initially, the long-term benefits are well worth it. Regular monitoring will ensure that no unauthorized services are inadvertently exposed.
Despite the simplicity of this recommendation, our penetration testing engagements frequently reveal an excessive number of published services, leading to successful breaches.
By adhering to the principle of least privilege and minimizing your public footprint, you can substantially strengthen your organization’s cybersecurity.
2. Implement Effective Software Update Management
Timely software updates are crucial for protecting your external network from breaches.
Vulnerabilities in software, stemming from errors made during development, are one of the four main causes of successful breaches.
Establishing a robust process to monitor and promptly install software updates and security patches for all components of your public-facing systems and services is paramount.
When utilizing third-party software, it’s nearly impossible to scrutinize every program for zero-day vulnerabilities. However, by implementing an effective software update management process, you can maintain control over the software used in your external network and ensure that all updates and patches are applied. This proactive approach can significantly reduce the risks of breaches and compromises.
For large enterprises, this process can be resource-intensive and time-consuming. However, if you’re just starting to develop your cybersecurity strategy, prioritize establishing this process for your external network first.
It will be quicker and easier than attempting to implement it across your entire IT infrastructure at once, yet it will still substantially elevate your protection level on an ongoing basis.
3. Establish a Comprehensive Password Policy
Almost every external network has services that require authentication for users, administrators, or other services. Implementing a strict password policy is essential, but it goes beyond just setting requirements for password complexity and lockout settings, as you might find in Active Directory.
95% of our penetration testing assessments are accompanied by password compromise
A comprehensive password policy is a complex document that extensively covers the use of passwords throughout your organization. To ensure its effectiveness, corresponding processes and technical controls must be in place to guarantee compliance with the policy’s provisions.
Here are some key elements to consider when creating your password policy:
- Define requirements for password complexity during account creation, storage (including configuration files, databases, scripts, mailboxes, etc.), and network transmission.
- Apply the policy to user passwords, IT administrator passwords, and service account passwords used by applications.
- Enforce the policy across all systems, including those managed by your staff and those maintained by service providers, hosting providers, external developers, etc.
- Implement strict protection against password guessing attacks, disable unused accounts, and change default passwords for all systems that require user authentication.
- Include requirements for user awareness training procedures.
- Restrict the use of outdated, unencrypted, and insecure protocols and technologies.
- Mandate the implementation of two-factor authentication for critical IT services and, ideally, for all services that require authentication in the external network.
- Prohibit the use of simple passwords that formally meet complexity criteria but are easily guessable, such as “Company1!”
Once you’ve defined and approved your password policy, the real work begins. You’ll need to bring your infrastructure into compliance with the policy’s provisions. While this may require significant effort, the benefits to your organization’s cybersecurity posture are well worth it.
4. Implement System Hardening
Hardening involves properly configuring each component of every individual service and applying best practices to ensure protection and implement cybersecurity controls. While this step can be complex and time-consuming, especially for large external networks, it’s essential for maintaining a strong security posture.
Let’s take a simple example to illustrate this concept. Suppose you have a web application running on the Django framework published in your IT infrastructure perimeter.
A quick Google search for “Django hardening” yields two informative resources:
These articles provide detailed information about the security technologies already present in Django and offer recommendations on how to apply these controls to ensure a high level of protection. They cover topics such as:
🔹 General Recommendations 🔹 Authentication 🔹 Key Management 🔹 Session Security 🔹 Headers 🔹 Cookies 🔹 Cross-Site Request Forgery (CSRF) 🔹 Cross-Site Scripting (XSS) 🔹 SQL Injection Protection 🔹 HTTPS 🔹 Admin Panel 🔹 Additional Security Topics
By applying these recommendations, you can further elevate the security level of your external network.
Keep in mind that System Hardening is not limited to web applications; it should be applied to all network services, infrastructure services, applications, and more.
Investing time and effort into System Hardening will pay off in the long run, as it helps create a more resilient and secure environment that can better withstand potential attacks.
5. Implement a Robust Vulnerability Management Process
Vulnerability management involves identifying and addressing vulnerabilities in your public-facing systems. To effectively implement this process, you’ll need:
- Technical tools: Vulnerability scanning tools specialized in analyzing networks, applications, and system infrastructure.
- Comprehensive scope: Include your IT infrastructure perimeter and external IT systems, such as those located in cloud infrastructure and hosting provider platforms, in your scanning targets.
- Regular assessments: Perform vulnerability assessments at least once per quarter.
However, merely detecting vulnerabilities is not enough; it’s crucial to ensure their prompt remediation. To achieve this, implement:
- Organizational controls: Procedures and instructions that describe and regulate responsibilities, the process for conducting scans, validating the existence of vulnerabilities, remediating them, and verifying the successful remediation of identified vulnerabilities.
We also recommend alternating the scanners used in each new cycle, as no tool is perfect. Your goal is to ensure that nothing is overlooked during the assessment and that everything is under control.
By establishing a robust vulnerability management process, you’ll continuously identify and address potential weaknesses in your external network, significantly reducing the risk of successful breaches.
6. Conduct Regular Penetration Testing
Penetration testing of your external network, performed by an independent team with high expertise, is an opportunity to identify additional vulnerabilities that may not be covered by the previous steps. These could include architectural vulnerabilities or logical vulnerabilities that require the highest level of pentester expertise and manual analysis to detect and exploit.
Compromising a system and obtaining high privileges is rarely achieved through a single vulnerability that grants full access to the infrastructure. Often, penetration scenarios involve a chain of 10-20 vulnerabilities (most of which are not critical on their own) that, when combined and properly exploited, can lead to the compromise of your IT infrastructure.
This is why penetration testing is an irreplaceable component in proactively protecting your network. It helps identify complex attack paths that may not be apparent through regular vulnerability scans or automated tools.
Regarding the frequency of penetration testing, key standards and best practices recommend conducting a pentest at least once a year or after significant changes to your IT infrastructure. This ensures that your external network remains resilient against evolving threats and newly discovered vulnerabilities.
If you require assistance with penetration testing services, feel free to reach out to us at XRAY CyberSecurity. Our team of experienced professionals is ready to help you identify and address potential vulnerabilities in your external network.
7. Balance Security and Usability
When implementing cybersecurity measures, it’s crucial to maintain a balance between security and usability.
Businesses always want everything to work quickly and seamlessly, while security teams often aim to restrict access as much as possible, following the “Deny S:Any D:Any” principle. Finding the right balance is crucial for effective cybersecurity.
This leads us to the importance of Risk Management. While this topic is too extensive to cover in a short article, we can discuss some key elements:
- Prioritize your security efforts: Don’t waste time on vulnerabilities with minimal likelihood of exploitation and minimal potential damage when there are other risks with more significant potential consequences for your business.
- When addressing risks, you have four options:
- Reduce: Implement counter-measures, such as additional technical controls, to minimize the risk.
- Avoid: Eliminate the risk by discontinuing the activity or process that introduces it.
- Transfer: Share the risk with a third party, such as an insurance company, to minimize the potential impact on your organization.
- Accept: Acknowledge and accept the risk, deciding not to take any action due to the low likelihood or impact of the risk.
This means that it may not always be necessary to apply counter-measures for every risk or vulnerability. Implement cybersecurity wisely, considering the feasibility and appropriateness of each action.
Conclusion
Securing your external network is a continuous process that requires a multi-faceted approach.
By minimizing your attack surface, implementing effective software update management, establishing a comprehensive password policy, implementing a robust vulnerability management process, conducting regular penetration testing, applying system hardening techniques, and balancing security and usability, you can significantly enhance your organization’s cybersecurity posture.
Remember, cybersecurity is a journey, not a destination.
It requires ongoing effort, adaptation, and vigilance to stay ahead of evolving threats.
By following the recommendations outlined in this guide, you’ll be well-equipped to protect your valuable assets and maintain the trust of your customers and stakeholders.
If you need assistance in securing your external network or conducting a professional penetration test, our team at XRAY CyberSecurity is here to help. With our expertise and commitment to delivering high-quality services, we can help you identify and address potential vulnerabilities before they can be exploited by malicious actors.
Contact us today to learn more about how we can support your cybersecurity efforts.
