A large attack surface poses significant security risks for organizations because It provides hackers with numerous opportunities to access your sensitive data. To mitigate the number of potential sensitive resource access points and reduce the risk of data breaches, organizations must follow the essential cybersecurity practice of attack surface compression.
Refer to the following list of attack surface reduction examples for ideas about further compressing your organization's attack surface and threat exposure.
18 Effective Examples of Attack Surface Reduction in 2023
1. Identify Assets that don't Need to be Connected to the Internet
Disconnecting unnecessary devices and systems from the internet can reduce the risk of cyberattacks. This includes limiting the number of integrations, web servers, interfaces, and IP addresses exposed to potential threats.
You can identify devices that could be culled from your attack surface by referring to your IT inventory. With a strong Shadow IT policy, this document should accurately reflect all approved devices in your attack surface. However, outside of a CISO's idealistic world, there will always be a discrepancy between an organization's IT inventory and its actual attack surface.
This is why attack surface reduction processes should augment attack surface management solutions that identify all IP addresses associated with your attack surface. Besides endpoints, these discoveries could include domains associated with vulnerable server software increasing your risk of suffering a data breach.
Watch the video below for tips on how to quickly reduce your attack surface.
2. Secure all Mobile Devices and Implement a Strong Device Policy
Establish a policy that details security protocols for device usage, including encryption requirements, approved applications, and mandatory use of VPN when connecting to public Wi-Fi. Also, consider implementing Mobile Device Management (MDM) solutions to control, enforce, and protect the organization's data on these devices.
3. Address Misconfigurations and Vulnerabilities
Detected vulnerabilities are the clearest indication of an excessive attack surface region that should be culled. A vulnerability scanner can automatically assess all of the domains and devices within your attack surface that contain exploitable security vulnerabilities.
An example of a vulnerability scanner is a security rating solution that quantifies security postures based on commonly exploited attack vectors and other unbiased factors.
4. Monitor for Shadow IT
Unapproved software and hardware introduce significant security risks to your organization. Use automated asset discovery tools to detect unauthorized software or hardware on your network. Implementing a streamlined process for requesting new software or hardware connections could be a quick solution to most Shadow IT instances.
5. Restrict USB Usage
In addition to seeking approval for connecting new USB devices, implement a policy that requires encryption for any data transferred from USBs. Also, consider disabling auto-run features for USB drives to prevent any potential malware from automatically executing.
6. Secure Access Points and Implement Zero Trust Architecture
Employee accounts are keys to a private network, and without proper account security controls in place, they become excessively bloated regions of your attack surface. Multi-Factor Authentication (MFA) is one of the easiest and most effective methods of protecting an account from most compromise attempts.
To mitigate lateral network movement should hackers find a way of exploiting MFA, a Zero-Trust architecture should be implemented. A Zero-Trust architecture is like extending MFA across all regions of your private network. With Zero-Trust, all users and devices are required to continuously authenticate themselves to justify their access to a network.
7. Conduct Attack Surface Analysis
Regularly perform attack surface assessments to identify potential vulnerabilities and areas for improvement. This should not be a one-time activity but a regular practice. Use automated tools to continuously monitor your attack surface and identify new risks as they emerge.
8. Implement Attack Surface Reduction Rules
Use tools like Group Policy and Intune to enforce security policies that minimize your organization's attack surface. Ensure these rules cover user behavior, system configuration, and network connections.
9. Manage Permissions and User Access
Regularly review user permissions and implement the principle of least privilege, which limits users' access to only the resources necessary for their job functions. Implement a system that provides regular reports on user permissions and flags any excessive or abnormal permissions for review. Consider implementing Role-Based Access Control (RBAC) to streamline user permissions management.
10. Secure Physical Attack Surface
Implement measures to protect against physical threats, such as unauthorized access to data centers or server rooms.
11. Address Potential Vulnerabilities in Web Applications and Servers
Regularly test and update web applications and servers to minimize the risk of unauthorized access and data breaches. This will involve Implementing physical security measures such as surveillance cameras, biometric access controls, and alarm systems.
Since these devices will inevitably expand your attack surface, they should be carefully assessed against your risk appetite to ensure their risk exposure doesn't outweigh their attack mitigation benefits.
12. Implement Strong Password Policies
Require users to create complex and unique passwords to prevent account compromise due to weak passwords. To eradicate the risk of weak passwords, use password management solutions that generate, store, and autofill complex passwords; and educate users on the importance of not reusing passwords across different systems.
13. Educate Employees about Social Engineering & Phishing
Train employees to recognize and avoid phishing attacks - one of the most common initial attack vectors leading to data breaches and ransomware attacks. These types of attacks target credentials for beaching any gateways on the digital attack surface. These could include firewalls, VPNs, and even security teams operating systems, such as antivirus software, Microsoft Defender, and vulnerability management programs.
Regularly conduct simulated social engineering and phishing attacks to test employee resilience against evolving tactics. With the support of ChatGPT, you can establish an in-house phishing simulation program at a fraction of the cost of hiring a third-party service. Read this post to learn how.
Your ransomware attack surface can be further reduced by scanning the dark web for evidence of sensitive data dumps following a ransomware attack. This specific disciple of data leak detection is known as ransomware blog data leak detection, because ransomware gangs usually publish details about stolen data on their ransomware blogs.
14. Adopt the Principle of Ongoing Attack Surface Management
Following the successful detection and remediation of detected cyber risks, Implement a mechanism for continuously monitoring evolving security threats, both internally and throughout the third-party network.
Ongoing monitoring is a tenant of Vendor Risk Management, a cybersecurity discipline with increasing emphases across regulations.
15. Implement Network Segmentation
Divide your network into smaller segments to reduce the potential of sensitive data compromise if your network is breached. Segmentation rules should be regularly reviewed as your network evolves.
To check whether a network has been sufficiently segmented, have penetration testers attempt to access the sensitive network regions they're designed to obfuscate.
16. Regularly Patch and Update Software and Hardware
Keeping all software, firmware, and hardware up-to-date with the latest security patches is one of the easiest methods of addressing the security risks of third-party solutions. It costs you nothing and allows you to benefit from the cybersecurity investments of your third-party providers.
17. Develop an Incident Response Plan
Create a comprehensive incident response plan outlining the steps to be taken during a security breach. This should include communication protocols, roles and responsibilities, and recovery procedures. A well-designed IRP will shut down active cyber threats before they have a detrimental impact on your sensitive resources - helping you achieve an outcome that's equivalent to a smaller attack surface.
Regularly conduct drills to test the response plan's execution time and make necessary improvements based on feedback from these drills.
18. Perform Regular Security Audits and Penetration Testing
Penetration tests will uncover any gaps in your security control strategy that represent excessive attack surface exposure. To remove the risk of bias, these tests should be performed by independent third parties. Penetration tests should be performed regularly to ensure your attack surface is kept minimal at all times.
Remember, all penetration tests should be considered successful - those that fail to compromise your data and those that succeed. A successful simulated breach is an opportunity to secure a potential pathway before a real hacker discovers and exploits it.