(Bill Buchanan’s article from the ABC NEWS AUS on December 21, 2017.)
Several video streaming sites and the popular file
sharing network The Pirate Bay have allegedly been "cryptojacking"
their users' computers in this way, as has the free wi-fi provider in a
Starbucks cafe in Argentina.
Users may object to this, especially if it slows down their computers. But given how hard it is for most companies to make money from online advertising, it might be something we have to get used to — unless we want to start paying more for things.
What is bitcoin?
Bitcoin is a digital cryptocurrency. It operates on a decentralised
peer-to-peer network, with no central authority or government backing. It can
be bought with fiat currencies like Australian dollars from online exchanges or
created through mining
Units of
cryptocurrencies such as bitcoin aren't created by a central bank like regular
money but are generated or "mined" by computers solving complex
equations. Cryptojacking involves using someone's computer without their
knowledge, perhaps for just seconds at a time, to mine a cryptocurrency.
In the case of
bitcoin, mining requires specialised hardware and consumes masses of energy.
For example, each bitcoin transaction takes enough energy to boil about 36,000
kettles filled with water. In a year, the whole bitcoin mining network consumes
more energy than Ireland.
But bitcoin is
not the only show in town and there are many competing cryptocurrencies. One of
the most successful is Monero, which builds a degree of privacy into
transactions (something bitcoin doesn't do). Currently it requires no
specialised hardware for mining, so anyone with computing power to spare can
mine it.
Mining usually
takes the form of a competition. Whichever computer solves the equation the
fastest is rewarded with the money. With Moreno and other similar
cryptocurrencies, a pool of computers can work together and share the reward if
they win the competition.
This allows individual computers to work on just a
small part of the mining task. The larger the pool, the more chance there is of
winning the reward. When a computer is cryptojacked, it is added to a pool to
work on the task.
One estimate is that 220 of the top 1,000 websites
in the world are conducting cryptojacking, making a total of $US43,000 over a
three-week period. This might not be very much but file-sharing sites in
particular have been searching for new business models in order to support
their operations and cryptojacking could grow into a new income source.
The problem for
the computer's owner is that this takes up processor power, making other
operations take much longer. Pirate Bay users have complained that their
processors have been using up to 85 per cent of their capacity compared with
less than 10 per cent for normal operations. This can be accompanied by a large
battery drain.
The Pirate Bay
has since said this high processor usage was a bug and the system should
normally use between 20 per cent and 30 per cent of processing power.
How do you avoid
being cryptojacked? Coinhive strongly advises websites that deploy it to inform
users they are being cryptojacked. But it's common for the code to run without
users realising and without a way to opt out of it. If you want to prevent your
computer from being cryptojacked you need a software tool which checks the code
as it runs, such as an ad-blocker.
But you might
feel that allowing a site to use a little bit of your computer's processing
power is a better alternative to being bombarded with advertising. Whatever you
do, you'll likely end up paying for "free" services somehow.
(Bill Buchanan is head of Edinburgh Napier
University's Cyber Academy.)
