Is it really useful to "unplug the network cable" after multiple variants of ransomware appear?

On May 15, the person in charge of the Network Security Coordination Bureau of the Central Network Information Office responded to the "worm" ransomware attack, saying that the ransomware was still spreading, but the spreading speed had obviously slowed down. At the same time, however, the monitoring of the National Network and Information Security Information Notification Center found that there are many varieties of WannaCry ransomware, such as changing the domain name and changing the receiving address, but the main transmission mechanism and destruction mode have not changed, and the threat still exists.

After the virus invaded, multipoint network security issued a plan to deal with the virus "attack": first unplug the network cable, install the patch, then back up the file, connect to the network, and then it was widely forwarded by netizens. Zheng, a network security expert, told Major Crimes Unit No.37 that the key of this method is to install patches in time to repair system vulnerabilities after the network is disconnected.

On May 15, Hainan Netan issued a security announcement that ransomware broke out. On Monday, all units unplugged the network cable, installed the windows patch, and backed up the files before turning on the computer. Subsequently, the Network Information Office of Shenzhen, Chongqing Netan and Chengdu Municipal Committee also issued similar notices to answer specific measures to prevent ransomware. In Weibo and the circle of friends, the news of "disconnecting the network before turning it on" was widely forwarded by netizens.

Zheng Xiang, a network security expert, explained to No.37 Major Crimes Unit that this scheme is indeed feasible. Because non-professionals and individuals can't judge whether the computer is open to ports such as 445, they can unplug the network cable to prevent virus intrusion, then install patches, back up files, and finally reconnect to the network. But the most important thing is to upgrade the computer system as soon as possible or fix the system loopholes with CD-ROM patches.