Faced with diminishing returns from ransomware and crypto jacking, cybercriminals are now raking in millions with formjacking, a new report has said.
Formjacking attacks are essentially virtual ATM skimming where cybercriminals inject malicious code into retailers' websites to steal shoppers' payment card details.
On an average, more than 4,800 unique websites are compromised with formjacking code every month globally, said cybersecurity research firm Symantec in its report "Internet Security Threat Report (ISTR)" on Sunday.
Symantec blocked more than 3.7 million formjacking attacks on endpoints in 2018, with nearly a third of all detections occurring during the busiest online shopping period of the year - November and December.
"Formjacking represents a serious threat for both businesses and consumers," said Greg Clark, Chief Executive Officer, Symantec.
"For enterprises, the skyrocketing increase in formjacking reflects the growing risk of supply chain attacks, not to mention the reputational and liability risks businesses face when compromised," he added.
The report analysed data from Symantec's "Global Intelligence Network", the largest civilian threat intelligence network in the world, which records events from 123 million attack sensors worldwide, blocks 142 million threats daily and monitors threat activities in more than 157 countries.
While a number of well-known retailers' online payment websites, including Ticketmaster and British Airways, were compromised with formjacking code in recent months, Symantec's research revealed small and medium-sized retailers are, by and large, the most widely compromised.
"By conservative estimates, cybercriminals may have collected tens of millions of dollars last year, stealing consumers' financial and personal information through credit card fraud and sales on the dark web," the report noted.
With more than 380,000 credit cards stolen, the British Airways attack alone may have allowed criminals to net more than $17 million.
In recent years, ransomware and cryptojacking, where cybercriminals harness stolen processing power and cloud CPU usage from consumers and enterprises to mine cryptocurrency, were the favourites among cybercriminals.
For the first time since 2013, ransomware infections declined, dropping by 20 per cent.Although cryptojacking activity peaked early last year, it declined by 52 per cent throughout the course of 2018.