Last week news broke that government supercomputers in Russia had been turned into cryptocurrency miners, now comes news that many UK government websites have been infected with cryptocurrency mining code.
More than 4,200 Websites Infected with Cryptocurrency Mining Code
The latest attack affects government websites around the globe, with more than 4,200 websites turning visitors’ computers into cryptocurrency miners.
The attack involved a popular website plugin called Browsealoud. Browsealoud is used to convert written website content into audio for the blind and partially sighted. The browser plugin was compromised by hackers who altered the source code of the plugin to include cryptocurrency mining code. By altering the plugin, the malicious code runs every time a site user visits a webpage that offers the audio function using the Browsealoud plugin.
When a visitor arrived at such as webpage, the code ran and turned that user’s computer into a cryptocurrency miner, using the computer’s processing power to mine Monero. Mining is the term given to verifying cryptocurrency transfers. Mining requires a computer to solve a complex problem. Once that problem is solved, the miner is rewarded with a small payment. In this case, the individual(s) who altered the code.
Using one computer to mine cryptocurrency will only generate a small return. However, by hijacking a browser plugin on a website that is visited by many thousands of individuals, the potential returns are considerable. The processing power of millions of computers can be harnessed.
Browsealoud was developed by the British company Texthelp. According to its website, its plugin has been installed on 4,275 domains. In the United Kingdom, many government websites use the plugin, including the Financial Ombudsman Service, the Information Commissioner’s Office, the Student Loans Company, many National Health Service (NHS) websites, and local government websites including the .gov.uk sites used by Camden, Croydon, Manchester, and Newham to name but a few. Many federal and state government websites in the US have turned their visitors’ devices into cryptocurrency miners, and it is the same story in Australia, Ireland, Sweden, and beyond.
The Browsealoud plugin is understood to have been infected with cryptocurrency mining code at some point between 0300 and 1145 UTC on February 11, 2018. The code was only active for a few hours before the change was identified and Texthelp disabled the plugin.
The mining only took place while a visitor was on a webpage that used the Browsealoud plugin. As soon as the tab or browser was closed, the mining stopped. Visiting the website that had been infected with cryptocurrency mining code via the plugin would not result in a malware infection. The only noticeable effect for any visitors to the websites would have been a slowing down of their computers or the fan starting as their computer started going into overdrive.
This incident has however made it quite clear to government agencies that their websites are not secure and using third party plugins on their sites to improve services for website users introduces risk.
These supply-chain attacks exploit a trusted relationship between the website owner and a third-party software/plugin supplier and the benefits for cybercriminals are clear. All it takes is for one plugin to be hacked to have malicious code run on many thousands of websites, thus targeting millions of website visitors. In this case, the damage caused was minimal, but the attack could have been much worse. The goal on this occasion was to mine cryptocurrency. The attackers could easily have inserted much more malicious code and attempted to steal login credentials.
That means a new hash is required if the vendor does not include a version number in their updated code. However, it will ensure that attacks such as this, or worse attacks with much more malicious code, will be blocked.