Growth Central

CloudFrunt - A Tool For Identifying Misconfigured CloudFront Domains

CloudFrunt is a tool for identifying misconfigured CloudFront domains.

Background

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:

If the HOST header does not match an entry in the "Alternate Domain Names (CNAMEs)" field of the intended distribution, the request will fail.
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.

Installation

$ pip install boto3
$ pip install netaddr
$ pip install dnspython
$ git clone https://github.com/disloops/cloudfrunt.git
$ cd cloudfrunt
$ git clone https://github.com/darkoperator/dnsrecon.git

CloudFrunt expects the dnsrecon script to be cloned into a subdirectory called dnsrecon.

Usage

cloudfrunt.py [-h] [-l TARGET_FILE] [-d DOMAINS] [-o ORIGIN] [-i ORIGIN_ID] [-s] [-N]

-h, --help                      Show this message and exit
-s, --save                      Save the results to results.txt
-N, --no-dns                    Do not use dnsrecon to expand scope
-l, --target-file TARGET_FILE   File containing a list of domains (one per line)
-d, --domains DOMAINS           Comma-separated list of domains to scan
-o, --origin ORIGIN             Add vulnerable domains to new distributions with this origin
-i, --origin-id ORIGIN_ID       The origin ID to use with new distributions

Example

$ python cloudfrunt.py -o cloudfrunt.com.s3-website-us-east-1.amazonaws.com -i S3-cloudfrunt -l list.txt

 CloudFrunt v1.0.3

 [+] Enumerating DNS entries for google.com
 [-] No issues found for google.com

 [+] Enumerating DNS entries for disloops.com
 [+] Found CloudFront domain --> cdn.disloops.com
 [+] Found CloudFront domain --> test.disloops.com
 [-] Potentially misconfigured CloudFront domains:
 [#] --> test.disloops.com
 [+] Created new CloudFront distribution EXBC12DE3F45G
 [+] Added test.disloops.com to CloudFront distribution EXBC12DE3F45G

Download CloudFrunt

Related posts

BASICS OF METASPLOIT – BASIC COMMANDS OF METASPLOIT

Metasploit is an advanced hacking tool that comes itself with a complete lack of advanced penetration testing tools. Penetration testers and hackers are taking so much advantage of this tool. It's a complete hack pack for a hacker that he can play almost any attack with it. Here I am going to discuss the basics of Metasploit. I am not covering attacks in this article, as I am just making sure to share the basics of Metasploit and basic commands of Metasploit. So, we can get back to cover attacks of Metasploit in the next articles.

BASICS OF METASPLOIT

The Metasploit framework has three types of working environments.

msfconsole
msfcli interface
msfweb interface

However, the most preferred and used is the 'msfconsole'. It's a very efficient command-line interface that has its own set of commands and system's working environment.

First of all, it's most important to know and understand all the useful commands of Metasploit that are going to be used.

BASIC COMMANDS OF METASPLOIT

Metasploit have a huge number of command that we can use in different type of attacks, but I am just going to share the most used and useful commands here that a beginner can easily understand and follow 'em.

help (It will give the basic commands you need to launch an exploit.
search (Finds out the keywords in the selected attack method).
show exploits (Shows list of an available exploit in the selected option).
show payloads (It lists all the payloads available).
show options (It helps you to know all the options if you might have forgotten one).
info (This is used to get information about any exploit or payload).
use (It tells Metasploit to use the exploit with the specified name).
set RHOST (Sets the address of specified remote host).
set RPORT (Sets up a port that connects to on the remote host).
set PAYLOAD (It sets the payload that gives you a shell when a service is exploited).
set LPORT (Sets the port number that the payload will open on the server when an exploit is exploited).
exploit (It actually exploits the service).
rexploit (Reloads your exploit code and then executes the exploit without restarting the console).

These are the most used Metasploit commands which come in handy in most of the situations during any sort of attack. You must give all the commands a try and understand 'em how it works and then move to the next part of designing an attack.

Related word

Video Archives Of Security Conferences And Workshops

Just some links for your enjoyment

List of security conferences in 2014

Video archives:

AIDE (Appalachian Institute of Digital Evidence)

Blackhat