Cloud computing has opened a new horizon towards the technical world and business that improves an organization’s accessibility, scalability, and cost efficiency. Cloud’s support for seamless online integration also improves collaboration efforts. However, as cloud servers store all data online and are mostly connected via numerous APIs to provide different functionalities, they also increase security surfaces compared to traditional monolithic architecture. Thus, it is essential for owners to implement strong Cloud Attack Surface Management solutions for brand protection.

In a recent webinar, Setu Parimi, co-founder and CTO at 1763986604-74d06f1bdede78c5.wp-transfer.sgvps.net, and Toni de la Fuente, the Founder and CEO of Prowler, discussed the top 10 best practices for Cloud Attack Surface Management. Drawing from their expertise and real-world experience, they shared valuable insights, tips, and practical solutions for securing cloud environments. Here’s a recap of the discussion:

10. Isolate Sensitive Resources in Private Networks

To minimize exposure, isolating sensitive resources in a private network is essential. As Tony explained, cloud providers like AWS have introduced Virtual Private Clouds (VPCs) to help achieve this. VPC is a kind of replica of the traditional network that is used to store and share resources in a private cloud, which allows an added layer of security and privacy from other organizations sharing these resources. These Virtual Private Clouds consist of one or multiple IP ranges, also known as subnets. Subnets can be further separated into four different groups: Public subnet, Private subnet, VPN-only subnet, and Isolated subnet, based on their configuration routing.

Setting up sensitive information on a private subnet network helps businesses isolate their resources from the rest of the internet, offering an added layer of security to them. During the panel discussion, Toni emphasized the importance of segregating resources in private subnets, saying, “The good practice is to put those resources into the private subnet. That is the takeaway here.” This approach allows organizations to control access to sensitive data, ensuring it’s only accessible through secure, monitored channels like bastion hosts or AWS Systems Manager (SSM). Cloud shell, a shell within the container in the owner’s account, can also be a good alternative to be used to navigate anywhere within a Virtual Private Cloud.

9. Least Privilege by Default for Cloud Attack Surface Management

The Principle of Least Principle or PoLP is a cybersecurity practice that focuses on allowing end-users access only to the information required to perform their tasks. Applying the principle of least privilege is a core tenet of cloud security, especially for Identity and Access Management (IAM). Setu shared his perspective on this, noting, “IAM is the most difficult thing to get right… because of the number of services and APIs available.” He continued, “If you get IAM and resource policy right, the attack surface will drastically reduce.”

PoLP also extends to the Zero Trust Network (ZTN), where administrators are not required to worry about the network constructs and can implement fine-grained access control for improved and secured least privileged access. He recommended implementing Service Control Policies (SCPs) across your organization to enforce these restrictions, helping limit exposure to only what’s essential for the roles or services in question. Limited privilege does not only prevent unauthorized access within your organization but also aids in third-party risk management. 

8. Continuous Asset Discovery and Inventory Management

Cybersecurity Asset Management or CSAM is a security method that focuses on continuously tracking the inventory, and online assets, and managing them for brand protection. Keeping track of all cloud resources is vital to maintaining a secure environment and addressing the security gaps with precision. Setu highlighted the importance of knowing what assets are in use, saying, “You can’t secure something that you don’t know.” Automating asset discovery is crucial, given the nature of cloud environments where resources can be short-lived. Solutions like AWS Config, Google Security Command Center, and Azure Security Center can help keep track of assets, ensuring there are no blind spots.

7. Enable Continuous Monitoring and Configuration Management

Security Configuration Management or SCM is a cybersecurity practice that involves continuous monitoring of the system assets and software configuration to identify misconfigurations. Configuration drift and misconfigurations are major security risks in the cloud. By monitoring configurations continuously, you can quickly identify and address security gaps in the organization’s network and help in Cloud Attack Surface Management.

As Toni pointed out during the panel discussion, “Monitoring changes in a security group or an S3 bucket policy is key,” as these changes directly impact security. Automating alerts for critical resources, such as VPCs, security groups, and routing tables, allows organizations to respond swiftly to potential threats.

6. Web Application Firewalls (WAF) to Protect Web Applications

Web Application Firewalls or WAFs are cybersecurity measure that protects your brand and assets from malicious websites and unreliable URLs by blocking suspicious HTTPs and preventing unauthorized data access by third-party applications. Securing web applications with a WAF is essential to filtering traffic and blocking potential threats. Web Application Firewalls provide added protection for web applications from different types of potential cyber threats like cross-site scripting or XSS, cookie poisoning, DNS poisoning, SQL injection, cross-site forgery, file inclusion, etc.

Setu shared a practical tip for implementing Web Application Firewalls, “If there are applications behind a load balancer, add a web application firewall on top of the load balancer.” Most cloud providers, such as AWS, Azure, and Google Cloud, offer native WAF solutions that come with pre-configured rules to block common vulnerabilities and bot traffic.

5. Resource-Level Identity and Access Management Policies

Resources in the Identity and Access Management policy are used to manage permissions and control third-party services like the KMS key or S3 Bucket. Resource-level Identity and Access Management policies add a layer of granularity to access controls, particularly for services like S3 and KMS. During the live panel discussion, Setu, the CTO of 1763986604-74d06f1bdede78c5.wp-transfer.sgvps.net mentioned a hack to prevent cross-account breaches using a new IAM Condition (aws:PrincipalOrgID) in AWS service control policies where “You can limit the IAM roles or S3 buckets being accessible only within the AWS account under a single organization.” He recommended using service control policies to prevent accidental misconfigurations and ensuring that data resources are accessible only within specified boundaries.

4. Enable Threat Detection and Intrusion Prevention Systems (IPS)

Monitoring for suspicious activity is fundamental to cloud security. Intrusion Prevention systems or IPS are implemented on a network system to detect threats in real-time and apply precautionary measures as required. This method helps detect threats before they can intrude and manipulate the system and cause real damage to the brand’s properties. These solutions can also be implemented to detect weak links in a network system and prevent exploitations by external actors. Toni shared the importance of leveraging native cloud security tools, such as AWS GuardDuty and Google Cloud IDS, noting, “GuardDuty can detect a good amount of unusual activity by monitoring DNS, CloudTrail, and API traffic.” These tools provide insights into potential threats, such as unauthorized API calls or unusual network traffic, enabling organizations to respond promptly.

3. Utilize Infrastructure as Code (IaC) with Security Automation

Infrastructure as Code or IaC allows organizations to automate infrastructure provisioning while applying security policies systematically. Under this security method, a consistent and scalable cloud security coverage is implemented that detects misconfiguration right at the development stages to prevent issues at runtime. Organizations can implement IAC throughout their development lifecycle with the code repositories, CI/CD practices, or in developer IDEs.

As Setu put it, “Avoid Click Ops as much as possible. Write your infrastructure as code and enforce security configurations by default.” By automating infrastructure deployment, organizations can enforce consistent configurations across environments, reducing the risk of misconfigurations.

2. Secure Internal Traffic Using VPC Endpoints

The resources added to a Virtual Private Cloud subnet typically do not have internet access. However, adding VPC endpoints to the subnet will allow those resources to communicate with one another without having to use the internet. Virtual Private Cloud endpoints allow users to connect supported services within a network using private links and route internal traffic within the data center, reducing latency and exposure to external threats. Setu pointed out that many people overlook this capability, saying, “With VPC endpoints, you can route traffic within the data center without leaving the cloud provider’s network.” This approach improves both security and performance, as traffic doesn’t traverse the public internet.

Setu also mentioned a quick tip during the conversation on helping EC2 servers communicate with S3 Bucket. He mentions that administrators can route the traffic within the AWS or Azure data center itself without leaving the provider’s server. All you will need to do is enable the endpoints and allow them to communicate with the S3 service. This practice can help you prevent any unencrypted traffic from your subnet from reaching the public internet.

1. External Cloud Attack Surface Management (CASM) Solution

While native cloud tools provide visibility, they leave a large number of access points online that can be manipulated by third-party malicious actors if not secured properly. Another security threat commonly faced by organizations comes from third-party service providers and vendors. Without proper vendor risk management measures, brands can fall prey to vulnerabilities coming from unprotected vendors.

External Cloud Attack Surface Management policies help businesses monitor their network continuously to detect any possible attack paths on the system. Using External Attack Surface Management solutions also helps businesses gain a third-party perspective to address potential vulnerabilities before an attack takes place. On addressing the importance of having an outside perspective Setu explained, “Having a different opinion on your cloud environment is healthy. It reveals blind spots that native tools might miss.” External Attack Surface Management solutions provide a fresh perspective, identifying exposed resources that may have been overlooked internally.

Conclusion

This informative webinar offered a wealth of insights into managing cloud attack surfaces effectively. As Setu and Toni demonstrated, maintaining a secure cloud environment requires a combination of native tools, third-party solutions, and well-structured policies. By following these best practices, organizations can reduce their cloud vulnerabilities and ensure that their data remains protected.