Cases of illegal apps and websites making unauthorized access to devices like smartphones and tablets to use their processing power for calculations to earn digital currency have been increasing, and data security companies are calling for users to exercise caution.
All of the exchanges of a digital currency are recorded in a public ledger called a "blockchain," and traders all over the world keep a shared copy of this ledger on their computers. When a new transaction is made, it is calculated against the existing data in the ledger and then added to the blockchain. The user who does this often complicated calculation and verifies the transaction is called a miner, and receives an amount of the digital currency in exchange for their work. This method of earning digital currency is called "mining."
Personal computers, smartphones, tablets -- even home appliances connected to the internet -- can be accessed and operated remotely for mining calculations. Some websites use devices for mining simply through having a user view the page. The process not only slows down the devices, but also opens the user up to personal information breaches.
According to major information security firm Trend Micro Inc., with the steep price rise of popular investment digital currency bitcoin, the variety of e-currencies is growing. Because of this, reports of fraudulent websites that send programs that force devices to do mining calculations began increasing domestically in May 2017, growing to 848 reported cases by September. In addition, fake websites that fraudulently use devices for mining just by having users view the site have also been confirmed.
In October 2017, a smartphone application for Google's Android operating system that automatically began using the device for mining once downloaded was discovered in the company's official application store. On top of that, when mining transfer conditions were investigated for the period between January and September 2017, some 6 percent of mining transmissions came from home appliances using the internet. It appears that the mining program had infiltrated webcams and video game systems.
An effected device does not undergo a large attack like when infected with virus software, but since mining focuses the use of a computer's central processing unit (CPU) for blockchain calculations, it slows down the speed of the device and also racks up electricity costs.
Meanwhile, when the digital currency payments received by miners was investigated, there were cases where the equivalent of some 20,000 yen was made in a single day.
"You can protect your devices (from being used for mining) by installing the most up-to-date security software and continuing to update your operating system," suggested a representative from Trend Micro.