CYBER criminals are launching a digital offensive in SA with attacks largely employing phishing tactics, says a tech company.

Data from internet security company Trend Micro shows that 6,185 local PCs were infected with banking malware in 2015. In the fourth quarter alone, 4,197 computers were infected with adware, and 6,564 with malware, said the company.

"In October 2015 the total malware count was 51,998; in November it was 44,645 and in December 43,724. A virus count in these three months found the numbers at 644, 566 and 637 respectively," Trend Micro said.

Cyber criminals largely employ two methods to steal data from South Africans, said the company.

"The first is phishing attacks where they use a blanket approach, sending malicious e-mails or files to as many users as possible and it’s obviously successful because cyber criminals are still using this method," said Darryn O’Brien, country manager at Trend Micro.

"The second method is spear phishing attacks, where hackers target one or two people, but that’s more time-consuming," he said.

The most common malware targeting locals was Dunihi followed closely by Dridex, and the most common adware was Opencandy, said Trend Micro.

Banking malware is directed to steal information such as usernames and passwords.

The primary delivery method of malware is spam and Trend Micro data showed that unsolicited mail in SA peaked in December with 2,269,039 messages, compared with 1,816,832 and 585,055 in October.

Security firm Kaspersky Lab recently warned that mobile apps downloaded from unofficial sources were known to have banking malware Acecard built in.