CloudFrunt

CloudFrunt addresses a critical security challenge in Amazon Web Services (AWS) by identifying and mitigating misconfigurations in CloudFront distributions. The core issue arises from how CloudFront uses the HOST header to determine which distribution to serve content from, rather than relying on the unique endpoint of the distribution. This can lead to domain hijacking if the "Alternate Domain Names (CNAMEs)" field is not properly configured.

Technically, CloudFrunt is a Python script that accepts a list of domains, either from a file or as a comma-separated list, and uses the dnsrecon tool to expand the scope of domains to check. It then filters these domains to identify those pointing to CloudFront IP space and tests them for configuration issues. The script can optionally create new CloudFront distributions and add vulnerable domains to these distributions to prevent hijacking.

Operationally, CloudFrunt requires careful setup, including cloning the dnsrecon script into a subdirectory and installing necessary dependencies. The tool is designed to run in parallel, making it efficient for large-scale scans, but this also means it can be resource-intensive. For example, a large-scale test involving 90,500 unique domains required an EC2 instance to manage the load.

Key technical details include the use of DNS reconnaissance to expand the domain list and the ability to save results to a file for further analysis. However, the tool's effectiveness depends on accurate input data and proper configuration of the CloudFront distributions. Limitations include the potential for false positives if DNS records are not up-to-date, and the need for careful management to avoid overwhelming AWS resources during large-scale scans. Additionally, the tool does not automatically fix all misconfigurations but rather identifies them, requiring manual intervention to secure the domains properly.