A report by IBM on Wednesday said that a total of 137.4 million cyber security attacks took place last year, averaging 380,000 on a daily basis.

The report, which was put together after researching 3,700 clients in 130 countries from Jan. 1-Dec. 31, 2012, said cyber attacks are “any kind of malicious activity that attempts to collect, disrupt, deny, degrade or destroy information system resources or the information itself.”

The most attacked industry was health and social services, which received an average 10.1 million attacks on a weekly basis, followed by the transportation and hospitality industries with 9.8 million and 5.5 million attacks every week, respectively, according to the report.

The finance and insurance sector as well as manufacturing were also found with 3.6 million and 2.6 million attacks, it said.

Up to 33 percent of the cyber attacks came in the form of malicious codes, while 28 percent were categorized as sustained probes or scans, it said. Fifteen percent were unauthorized access attacks and 12 percent were “low-and-slow” long-term attacks.

The report pointed out that 23 percent of the attacks were committed by malicious insiders although 44 percent were done by outsiders.

“While the inadvertent actor is the smallest group behind cyber security attacks, it is responsible for approximately 50.9 percent of inadvertent data leaks per week,” said the report.

Nearly half of the attackers carried out the cyber threat due to opportunistic reasons, it said, while 23 percent were motivated by industrial espionage, financial crime and data theft.

Another 15 percent launched the act because of dissatisfaction with their employers or the jobs, and 7 percent were motivated by social activism and civil disobedience.

The report also discovered that it took an average of $120,000 in botnet activity among other response costs to remediate incidents. Network compromise costs another $92,156, and malware infection and email compromise cost $61,875 and $33,000, respectively.

By Cho Ji-hyun (sharon@heraldcorp.com)