CloudFrunt – Identify Misconfigured CloudFront Domains


CloudFrunt is a Python-based tool for identifying misconfigured CloudFront domains, it uses DNS and looks for CNAMEs which may be allowed to be associated with CloudFront distributions. This effectively allows for domain hijacking.

CloudFrunt - Identify Misconfigured CloudFront Domains


How CloudFrunt Works For Misconfigured CloudFront

CloudFront is a Content Delivery Network (CDN) provided by Amazon Web Services (AWS). CloudFront users create “distributions” that serve content from specific sources (an S3 bucket, for example).

Each CloudFront distribution has a unique endpoint for users to point their DNS records to (ex. d111111abcdef8.cloudfront.net). All of the domains using a specific distribution need to be listed in the “Alternate Domain Names (CNAMEs)” field in the options for that distribution.

When a CloudFront endpoint receives a request, it does NOT automatically serve content from the corresponding distribution. Instead, CloudFront uses the HOST header of the request to determine which distribution to use. This means two things:

  1. If the HOST header does not match an entry in the “Alternate Domain Names (CNAMEs)” field of the intended distribution, the request will fail.
  2. Any other distribution that contains the specific domain in the HOST header will receive the request and respond to it normally.

This is what allows the domains to be hijacked. There are many cases where a CloudFront user fails to list all the necessary domains that might be received in the HOST header. For example:

  • The domain “test.disloops.com” is a CNAME record that points to “disloops.com”.
  • The “disloops.com” domain is set up to use a CloudFront distribution.
  • Because “test.disloops.com” was not added to the “Alternate Domain Names (CNAMEs)” field for the distribution, requests to “test.disloops.com” will fail.
  • Another user can create a CloudFront distribution and add “test.disloops.com” to the “Alternate Domain Names (CNAMEs)” field to hijack the domain.

This means that the unique endpoint that CloudFront binds to a single distribution is effectively meaningless. A request to one specific CloudFront subdomain is not limited to the distribution it is associated with.


CloudFrunt Usage to Identify Misconfigured CloudFront

After installing CloudFrunt and its dependencies you can run it with the following options:

CloudFrunt Usage

Related but not so similar is:

AWSBucketDump – AWS S3 Security Scanning Tool

You can download CloudFrunt here:

cloudfrunt-master.zip

Or read more here.

Posted in: Hacking Tools

, ,


Latest Posts:


HELK - Open Source Threat Hunting Platform HELK – Open Source Threat Hunting Platform
The Hunting ELK or simply the HELK is an Open-Source Threat Hunting Platform with advanced analytics capabilities such as SQL declarative language, graphing etc
trape - OSINT Analysis Tool For People Tracking Trape – OSINT Analysis Tool For People Tracking
Trape is an OSINT analysis tool, which allows people to track and execute intelligent social engineering attacks in real-time.
Fuzzilli - JavaScript Engine Fuzzing Library Fuzzilli – JavaScript Engine Fuzzing Library
Fuzzilii is a JavaScript engine fuzzing library, it's a coverage-guided fuzzer for dynamic language interpreters based on a custom intermediate language.
OWASP APICheck - HTTP API DevSecOps Toolset OWASP APICheck – HTTP API DevSecOps Toolset
APICheck is an HTTP API DevSecOps toolset, it integrates existing tools, creates execution chains easily and is designed for integration with 3rd parties.
trident - Automated Password Spraying Tool trident – Automated Password Spraying Tool
The Trident project is an automated password spraying tool developed to be deployed on multiple cloud providers and provides advanced options around scheduling
tko-subs - Detect & Takeover Subdomains With Dead DNS Records tko-subs – Detect & Takeover Subdomains With Dead DNS Records
tko-subs is a tool that helps you to detect & takeover subdomains with dead DNS records, this could be dangling CNAMEs point to hosting services and more.


Comments are closed.