Why write a bot that spams people with Viagra ads when you can write a bot that just wrings coins directly out of their computer chip?
For the uninitiated, Bitcoins are a digital currency that can be minted from excess CPU cycles of a computer and used in a variety of Internet contexts. More on Bitcoins:
http://www.nmdnet.org/2011/06/12/is-bitcoin-the-future-of-money/
So the money being “stolen” is not existing cash that is somehow withdrawn from your bank account or charged to your credit card, but is new money “printed” when your computer is hijacked by the malware.
This is kind of like breaking into an alchemist’s shop and making gold from his leftover iron.
GPGPU Bitcoin Mining Trojan
“Security researchers have unearthed a piece of malware that mints a digital currency known as Bitcoins by harnessing the immense power of an infected machine’s graphical processing units. According to new research from antivirus provider Symantec, Trojan.Badminer uses GPUs to generate virtual coins through a practice known as minting. That’s the term for solving difficult cryptographic proof-of-work problems and being rewarded with 50 Bitcoins for each per correct block.”