BEIJING: The number of computers in China under attack from ransomware dropped from Monday to Tuesday to 213,000 per hour on average from more than twice that at 520,000 per hour from Saturday to Sunday, according to data released by the National Computer Network Emergency Response Technical Team/Coordination Centre of China.
The drop is mainly because users of Windows operating systems have begun to install patches developed by Microsoft after the global attack over the weekend, said Zhang Shuai, an engineer from the centre on Wednesday, although risk remains high.
Gas stations run by China National Petroleum Corp in several cities could not carry out card and mobile payment transactions on Saturday because their computers were affected by ransomware, the company said. Schools in China also were hit hard over the weekend.
Via a security loophole in Windows, the virus encrypts the data and system files on the computer, which the user can access only by paying US$300 (RM1,298) via the anonymous online Bitcoin currency within seven days.
Zhang said Microsoft released patches to prevent such attacks in March and April.
Computers under attack are those that haven’t updated their systems on time.
Tests by researchers show that an unpatched computer that was connected to the Internet could be infected in a matter of minutes.
“WannaCry” targets files that are important to the users, such as Word documents, pictures and videos, Zhang said.
It is almost impossible to fully recover the files once they are locked by WannaCry, Zhang said. — China Daily/Asia News Network