As many as 250 customers at Sweden's largest bank seem to have downloaded files containing the 'haxdoor.ki' Trojan over the past three months. This fellow turned himself on when users tried to log in to their online account at the bank.
The software stole users' information before displaying an error message asking the client to resend the data. The hackers, believed to be based in Russia, then had the two access codes needed to transfer money from the account.
Swedish police have a list of 121 suspects, following a trail that led through servers in America, before being forwarded to Russia.
Insecurity firm McAfee said the attack highlights a worrisome trend.
"This is a worrying concern for any online bank user, as the threat of cyber-crime targeting 'safe' institutions becomes an ever more real concern," a spokesbloke said. µ
Sign up for INQbot – a weekly roundup of the best from the INQ