File picture: Dado Ruvic/Reuters

Johannesburg - It’s a gold rush that is turning computers into money-making machines, and the owners have no idea it's happening.

Across South Africa criminals are hacking into computers so they can use them to mine cryptocurrencies like Bitcoin. It's known as cryptojacking and it is taking off in South Africa. Over the past couple of weeks experts have noticed a marked rise in the crime as cyber prospectors try to cash in on the bitcoin craze.

Jacques van Heerden, chief executive of Global Technology Security Provider, says he knows of at least three companies that have been hit by cryptojacking locally. Banks have been targeted, too.

“It’s happening in banks as their computers have a lot of processing power,” says Van Heerden. “The more processing power you can get, the quicker you can make money.”

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Cryptocurrencies like Bitcoin are mined by a complicated process that involves transactions that are verified and then added to the public ledger, which is known as the block chain. Cyptocurrency mining is a process of compiling transactions into blocks and then trying to solve a puzzle. The rewards are newly released cyber currency. But to solve this puzzle requires using a large amount of computing power.

And cryptojackers are getting round this by hacking into and then harnessing the power of large groups of computers.

They do this, Van Heerden says, by planting a mining app on the PC. “That mining app will then run on the local PC that got compromised, and it will send all the cryptocurrency that it mined to an anonymous bitcoin wallet.”

Cyber investigators have also noted that IT personnel are using their own company computers to mine bitcoin.

“The CEO doesn’t necessarily know, even in smaller companies, what the IT guys are doing,” says Cyanre CEO Danny Myburgh. Recently Myburgh’s company was called in to investigate what they initially thought was malware that had been installed on a computer. They later discovered that it was an IT staff member who was using the network to mine bitcoins.

At first glance, cryptojacking might not appear to be a crime; after all the computer is being borrowed to make money. Often data isn't stolen and the computer isn't damaged. However, Myburgh says cyptojackers are breaking the law because they are hacking into a PC they don’t own and are using the data.

There are other dangers too. “It makes these computers susceptible to an external attack because if anyone scans the network and sees there is bitcoin mining going on, that could paint a target on an organisation,” says Myburgh.

Van Heerden says what is also concerning is that some cryptojackers are using tools that disable sophisticated antivirus software. “We were quite amazed at the technique they used and how easy it is,” he says.

Police officials are aware of cryptojacking.

Van Heerden says that one way of finding out if a computer is being covertly used to mine cybercurrencies is to see if the central processing unit is over-working.

“In a normal computer it should be working at between 10 and 40%. Where there is mining it will be running at 70% and above.”

Cryptojacking is still a new phenomenon in South Africa, but both Van Heerden and Myburgh believe it will continue to grow as more and more people see it as an easy way to make quick money.

Saturday Star