TLS 1.2 Proxy

TLS 1.2 Proxy
TLS 1.2 Proxy

Some of our customers have approached us at the start of 2018 with older software, and systems that suddenly stopped working because of the TLS 1.2 requirements. While this ultimately means the software, or, system is outdated and needs an upgrade. It's fair to say that not all companies follow security standards close enough to know of the change. Because of this, we have decided to create a simple open source solution that gives older software, and systems the ability function while their replacements are found.

One such example for one of our customers was that UPS in 2018 switched to supporting only TLS 1.2 or higher through https in there API systems. This caused many shipping rates calculating software including older websites to suddenly break.

While we do not consider this a secure solution for credit card processing (please don't do this!). This solution should be fine for simple processing such as news feeds, and simple API requests such as UPS, FedEx, OnTrac etc...

You can find the source code for the proxy at it's repository. Please note we do not guarantee a timeframe for fixes or feature requests on this project. You are free to fork, and modify the project as you see fit, however, we request that you please keep a link to the original repository.


Linux Users

  • Type the commands below into a shell window:
sudo apt update && sudo apt install git nodejs npm  
git clone  
chmod +x ./configure  
npm start  

Windows Users

npm start  

Hosting Certificate

This proxy is not exactly a MiTM attack in that it can't impersonate the certificate on X-Host. Instead it will create a physical TLS client and connect to X-Host on the requests behalf. It will then serve that request back to the original request's response with very limited rewrites of the Host header, and temporarily the Accept, and Accept-Encoding headers to prevent compression (not yet supported).

If you are using linux then 'configure' will give you the option of creating a self-signed certificate to host from. This will only work if you disable checking on the certificate in your code however. Instead it's highly advised to host the proxy on a domain with a valid certificate.

If your using windows then 'configure.bat' will not give you the option of creating a self-signed certificate but you can find many tutorials online for creating self-signed certificates in windows. The proxy is designed to use the windows pfx certificate format with a password.


The proxy does not limit connections by ip address, or filter to localhost. This because in all hosting cases you should have access to the systems firewall, or an external firewall unit. You can filter access to the port you have chosen using one of these methods rather than software doing it which is vulnerable to DDoS attacks.

In the event the proxy is public facing there is at least a basic concept of X-Key which will require that each request contain a matching key in the config file (an array so you can add as many as you need). However be advised this is just a basic security measure. It is not cryptographically secure because this would require a fair amount of code changes to legacy applications (which if there running in a version of a language that can't support TLS they absolutely are) which companies most likely will not authorize.


Proxy is designed to run at the port you configured it to run at. You can reach it using the https protocol only. Please read above about hosting certificates and security if you have not already.

The proxy will look for two headers OR querystring values with the names X-Host, and X-Key. These values will be removed before reaching X-Host. The values and there purpose with exmaples is explained below:


This can be either a querystring, or a header in the request. This value should contain the address (without http, or https) including the path. If this is missing requests will be terminated before processing.



This can be either a querystring, or a header in the request. The value should contain a key that matches one of the values in config.keys which can be modified in config.json which is setup with 'configure' or 'configure.bat'. If this is missing requests will be denied before processing.

Example: F4E9F81F-97EA-4720-A907-1A6E41E236B0


This is an example request to the proxy using querystring data. The querystring data can also be a header in request which is slightly harder to explain by example.

Note: The above address is not real. Additionally if your X-Host requires querystring data it's self, AND your chosing to use querystrings with the proxy you will need to first encode your querystring values with url encoding. It's however advised to use request headers if your X-Host requires querystring data to prevent any odd encoding issues.

Please report any issues to Github.

Timothy D Meadows II's Picture

Timothy D Meadows II