The State Bank of Vietnam has written to banks, credit institutions and financial organisations, warning them against hackers a day after the websites of Noi Bai and Tan Son Nhat airports and Vietnam Airlines were hacked.

It instructed them to review the safety of their networks, especially with respect to online customer service, and take the necessary steps to secure their IT systems and protect and recover databases if needed.

The SBV also ordered them to have technicians monitoring their IT systems constantly and improve oversight to discover attacks immediately.

‘Banks’ information technology systems will be very safe but users should secure all their private information when doing e-commerce transactions on the internet,” a leading IT expert told Labour newspaper.

A Techcombank official said, “Those who have paid through the Vietnam Airlines website might be at risk since hackers must have got access to their private information through the attack.”

Vu Ngoc Son, deputy chairman in charge of anti-malware at BKAV Technology Group, admitted this was a very serious attack and hackers have entered deep into the airlines database.

He told Vietnam News: “In Vietnam, most enterprises only invest in equipment and ignore online security. When they find an illegal attack, they do not know how to cope with it and it worsens the aftermath.

“Warnings about online security are still strange for most companies and organizations, and there will be more attacks if the situation does not change quickly.”

A senior banker said banks are realising that international and local criminals are using sophisticated methods to steal money from bank accounts and credit cards.

Online security experts said to safeguard their accounts and credit cards, customers should not take photos of cards and store them or share them on email or social networks.

Secondly, users must carefully check online shops before using their cards, should not provide their CVV numbers to dubious websites.

Thirdly, users must be cautious about promotions and advertisements coming by email, and never access any online shop or make online payment through a link. Instead, they should directly access the site by typing the address in the browser.

Fourthly, users should use and regularly update anti-virus, anti-malware, and anti-key logger software in their computers and mobile devices which are often used to access online shops.

Fifthly, users should never provide credit card information on the telephone or by email under any circumstances.

According to the international internet security firm Kaspersky, Vietnam is among the nations to suffer the most malware attacks.

The country is also No.1 in spreading viruses through external devices like USBs, memory cards, and mobile hard disk drives and 71 per cent of all computers are infected.

Around 40 per cent of users suffer from malware contracted online.

Last year 10,000 websites were hacked, an increase of 68 per cent from 2014, including 224 Government websites, though that number was down 11 per cent

“Many network equipment enterprises have been accused of already installing malware and backdoors on their equipment to easily hack,” Colonel Nguyen Van Thinh, deputy head of the Ministry of Public Security’s network security department, said.

VNS