According to a report by online security firm Trustwave, the 'Coinhive' crypto mining software was installed on all these devices through the infected routers in a large-scale attack carried out in July.Author of the report and security researcher at the company Simon Kenin said that all of the infected devices were seen using "the same sitekey". He also points out that as a result of the attack, one entity ended up reaping the mined tokens from all of these devices.
Stressing on the severity of the incident, he added that this attack may currently be prevalent in Brazil, but other geo-locations could also be affected as well, hinting at a possibility that the attack may have been intended to be on a global scale.
Cryptocurrency mining hacks like this have been a rising trend over the past two-three years as attackers shift from ransomware into the world of cryptomining.
Another post by Kenin said that Coinhive in 2017 claimed to offer solutions to monetise websites without the use of advertisements. Site owners ended up embedding a JavaScript code that would start controlling the CPUs of site visitors, and mine the cryptocurrency Monero in the process.
This mining reportedly brought the CPU processing power down by 99 percent, which led to other issues with devices getting hotter and using large amounts of electricity.
Other cybersecurity firms such as Skybox Security have also reported recently that crypto mining now accounts for 32 percent of all cyber attacks, and ransomware for 8 percent.