The government yesterday warned computer users to beware of this dangerous malware. Prime Minister Prayut Chan-o-cha has instructed the Ministry of Digital Economy and Society to closely monitor the situation here and issue guidelines necessary to the public to curb negative impacts, Government spokesman Lt-General Sansern Kaewkamnerd said yesterday.

Europol, the European Union’s law enforcement agency, said yesterday the cyber-attacks were causing havoc across the globe “at an unprecedented level”, AFP reported. The attacks would “require a complex international investigation to identify the culprits”, said the agency, which is working with countries and companies affected.

Some unidentified computers in Thailand were attacked by the WannaCry ransomware that has caused the attacks but critical sectors of healthcare, telecommunications and finance have not been affected, the Thailand Computer Emergency Response Team (ThaiCERT) said yesterday.

Ransomware is a type of malicious software designed to block access to a computer system until a sum of money is paid.

“In Thailand, we found that some computers were affected by the malware. But the infection has not been widespread,” ThaiCERT said in a statement. However, it did not have details regarding particular computers, IP addresses or organisations affected, a source familiar with the matter told The Nation yesterday.

The source said he saw a diagram that shows Thailand is among the countries targeted.

After learning about the attack, ThaiCERT alerted leading public hospitals but so far, no hospitals in Thailand have been hit by the ransomware attack, the source said. Financial services and banks, as well as the telecommunications sector, did not appear to have been affected.

“We had a meeting with hospitals on Saturday morning. The healthcare sector has not been affected,” the source said.

Local mobile operator, Total Access Communication Plc (Dtac) told The Nation the firm’s telecommunication network had not been attacked by WannaCry.

Kasikornbank said its system security team has measures to protect and closely monitor the bank’s computer systems.

Meanwhile, Vice Minister for Digital Economy and Society Pansak Siriruchatapong said critical infrastructure organisations – hospitals and financial institutions included – must have action plans to take care of their information.

As many as 90 per cent of computers affected by ransomware would not recover, according to the source. He said organisations could protect themselves from ransomware by updating information in an external hard disk, avoid opening attached files in emails sent from unknown senders or clicking suspicious links. They should also keep their operating system and other software updated, the source advised.

Organisations could help protect users from ransomware with a system to filter emails. Currently, most organisations in Thailand are aware of the risk of cyber-attacks, he added.

“The challenge is how to deal with the risk. To deal with the cyber-attack, organisations should be reactive, have a computer emergency response team or CERT team, and proactive action plans,” he said.

He suggested that financial, telecom, and healthcare sectors should have their own CERT – Computer Emergency Response Team.

ThaiCERT is closely working with financial institutions, including the three main regulators of the financial, stock, and insurance sectors.

Currently, 200 of the 283 state organisations use ThaiCERT’s security services. The Office of the Permanent Secretary for the Ministry of Public Health and King Chulalongkorn Memorial Hospital, were examples.