Hackers hide viruses in blockchains
They are the fundamental element of cryptocurrencies. But they can also have another use.
Blockchains are sets of blocks
of data, stored simultaneously on
many computers connected to the internet
– and impossible to alter once written.
They function as decentralized and secure
repositories for online information.
That's why blockchains are used to
record transactions with cryptocurrencies, such
as bitcoin. But they can also serve another purpose.
A group of security researchers from
Google discovered that hacker groups are
using blockchains to store viruses and
other attack tools. Blockchains
are beyond the reach of authorities, and they
cannot be deleted – which also applies
to any viruses stored in them.
The researchers also described
a technique, dubbed EtherHiding (referring
to the cryptocurrency ethereum), that allows
hiding viruses in "smart contracts":
legitimate software used to automatically transfer
cryptocurrencies between two
people when a certain condition
(such as providing a service, for example)
is met. With EtherHiding, a virus is
executed along with the contract. According to the
researchers, the technique is already being used
by North Korean hackers. (BG)
