Systems Hardening
What is Systems Hardening?
Systems hardening is a collection of cybersecurity tools, techniques, and best practices to reduce vulnerability in technology applications, systems, infrastructure, firmware, and other areas. The goal of systems hardening is to reduce risk by eliminating potential attack vectors and condensing the system’s attack surface. This process of removing superfluous programs, accounts functions, applications, ports, permissions, access, etc. strengthens security. It ensures that attackers and malware have fewer opportunities to gain a foothold within your IT ecosystem.
Systems hardening demands a methodical approach to audit, identify, close, and control potential security vulnerabilities throughout your organization. There are several types of system hardening activities, including:
Application hardening
Database hardening
Endpoint hardening
Identity hardening
Network hardening
Operating system hardening
Server hardening
Although the principles of system hardening are universal, specific tools and techniques vary depending on the type of hardening you are carrying out. System hardening is needed throughout the lifecycle of technology, from initial installation, through configuration, maintenance, and support, to end-of-life decommissioning. Systems hardening is also a requirement of mandates such as PCI DSS and HIPAA, and cyber insurers increasingly demand it.
How Do You Harden a System?
You harden a system by reducing the “attack surface,” the combination of all the potential flaws and backdoors in technology can be exploited by threat actors. These vulnerabilities can occur in many ways across infrastructure and identities. Some create direct or indirect escalation pathways that threat actors can use to fast-track attacks.
Common attack surface vulnerabilities include:
Default passwords – Attackers can leverage automated password crackers to guess the defaults. If the same defaults is used across different endpoints or accounts, ranging from desktops to IoT, the resulting attack surface can be very large.
Hardcoded passwords and other credentials stored in plain text files can increase the attack surface in a couple important ways. If they are forgotten in deployed code or otherwise publicly exposed, the hardcoded credentials can provide a backdoor into the organization.
Unpatched software and firmware vulnerabilities are historically one of the biggest contributors to attack surfaces. While patching will mitigate a vulnerability, patches are not always available as in the case of zero day threats. Moreover, some patches may be too disruptive to implement or not economically feasible.
Lack, or deficiency, of privileged access controls. With the expansion of the cloud and all things digital transformation, privileged accounts and access has exploded. The privileged account attack surface is not just humans and employees, but also increasingly involves machines and vendors. In cloud environments, privileged access and accounts may be dynamic and ephemeral, further complicating efforts to gain visibility and control over this massive risk.
Poorly configured BIOS, firewalls, ports, servers, switches, routers, or other parts of the infrastructure. With the strong growth in cloud and hybrid infrastructure, IT environments are becoming increasingly complex. This complexity is fertile ground for misconfigurations not only can cause systems to crash or misfire, but also can create dangerous security holes. Misconfigurations like open ports have resulted in some of the worst cloud breaches in recent years. For instance, they can inadvertently expose data buckets or provide publicly accessible backdoors to critical infrastructure.
Unencrypted, or inadequately encrypted, network traffic or data at rest can make it easy for attackers to access data or eavesdrop on conversations and access. They can then potentially gain important information (such as passwords) needed to advance an attack.
Additionally, the Center for Internet Security (CIS) maintains updated guidelines on their site around best practice system configurations for specific use cases. The CIS Benchmarks include over 100 guidelines across 25 vendor product families (Amazon Linux, Amazon AWS, Apple iOS, Apple macOS, Checkpoint Firewall, Cisco, Docker, Google Cloud, Microsoft Azure, etc.).
Systems Hardening Starts with Discovery. Get Started.
Reveal account misconfigurations, overprivileged accounts, unused accounts, stale passwords, & other potential identity-based backdoors.
10 Cybersecurity Best Practices for Systems Hardening
Several cybersecurity best practices can aid in hardening your systems and reducing your overall attack surface. The type of hardening you carry out depends on the risks in your existing technology, available resources, and the priority for making fixes.
1. Audit of existing systems. Carry out a comprehensive audit of your existing technology. Use penetration testing, vulnerability scanning, configuration management, and other security auditing tools to find flaws in the system and prioritize fixes. Conduct system hardening assessments against resources using industry standards from NIST, Microsoft, CIS, DISA, etc.
2. Strategic approach to systems hardening. You do not need to harden all your systems at once. Instead, create a strategy and plan based on risks identified within your technology ecosystem, and use a phased approach to remediate the biggest flaws.
3. Immediate vulnerability patching. Ensure you have an automated and comprehensive vulnerability identification and patching system in place. Systematically identify vulnerabilities and prioritize remediation. In some instances, vulnerabilities cannot be patched. In these cases, ensure that other mitigations are in place. Examples include removing admin rights—which many exploits require to exploit a vulnerability—and/or having cyber insurance in place.
4. Network hardening. Properly configure your firewall and regularly audit all rules. Secure remote access points and users. In addition, block any unused or unneeded open network ports, and disable and remove unnecessary protocols and services. Implement access lists and encrypt network traffic.
5. Server hardening. Put all company hosted servers in a secure datacenter and never test hardening on production servers. Always harden servers before connecting them to the internet or external networks. Avoid installing unnecessary software on a server and segregate servers appropriately. Properly set up superuser and administrative shares, limiting rights and access in line with the principle of least privilege.
With cloud environments, it is also particularly important to reduce port exposure so data is not inadvertently leaked, or backdoor access provided to infrastructure.
6. Endpoint hardening. Harden endpoints by removing local admin rights on all Windows and macOS endpoints, ensuring no workstations, laptops, or IoT have default passwords. Additionally, remove any unneeded software and block any unnecessary communications.
7. Application hardening. Harden applications by removing any unneeded components or functions, as well as restricting access to applications based on user roles and context (such as with application control). It's also important to remove all sample files and default passwords. Application passwords should then be managed via an application password management/privileged password management solution, that enforces password best practices (password rotation, length, etc.).
Hardening of applications should also entail inspecting integrations with other applications and systems and removing or reducing unnecessary integration components and privileges.
8. Database hardening. Create admin restrictions, such as by controlling privileged access, on what users can do in a database. Turn on node checking to verify applications and users. Encrypt database information—both in transit and at rest—and enforce secure passwords. Introduce role-based access control (RBAC) privileges and remove unused accounts.
9. Operating system hardening. Apply OS updates, service packs, and patches automatically. Additionally, remove unnecessary drivers, file sharing, libraries, software, services, and functionality. Encrypt local storage and tighten registry and other systems permissions as well. Log all activity, errors, and warnings and implement privileged user controls.
10. Identity hardening and elimination of unnecessary accounts and privileges. Enforce least privilege by removing unnecessary accounts (such as orphaned accounts and unused accounts) and privileges throughout your IT infrastructure. This is one of the most powerful security practices for reducing the attack surface.
Benefits of Systems Hardening
Systems hardening requires continuous effort, but the diligence will pay off in substantive ways across your organization via benefits such as:
Enhanced system functionality: Fewer programs and less functionality means there is less risk of operational issues, misconfigurations, incompatibilities, and compromise.
Significantly improved security: A reduced attack surface translates into a lower risk of data breaches, unauthorized access, systems hacking, or malware.
Simplified compliance and auditability: Fewer programs and accounts coupled with a less complex environment means auditing the environment will usually be more transparent and straightforward.
