WannaCry Computer Virus: How Did it Spread Worldwide?

Investigators are focusing on how a computer virus spread like wildfire over the weekend and impacted computers and networks in more than 150 countries.

The WannaCry virus locked up users' computers and demanded ransom payment in the form of Bitcoins, an online currency. According to The Wall Street Journal, authorities seem to have a handle on the path the virus took through computer networks.

Now they're attempting to find the first network affected by the virus, which could offer a clue as to who was behind it.

The Journal reports that the virus may have spread through Port 445, a port in computer networks that was not believed to be connected to the internet. That has investigators baffled as they try to follow the trail they hope leads to the source.

The European Union Agency for Network and Information Security (ENISA) said in a Monday morning statement an estimated 190,000 computers were hit with the virus, which infects machines running on Windows operating systems. The BBC reported that more than 200,000 computers were hit.

In a separate announcement, ENISA suggested to businesses with computer networks to "consider adding a rule on your router or firewall to block incoming SMB traffic on port 445 from untrusted sources."

The virus is a form of ransomware, which asks the users of infected computers for payment in order to unlock their computer files. Microsoft sent out a ransomware patch in February but not everyone installed it, which left computers vulnerable.

• Malware Attack Kill Switch Halts Spread of Ransomware in US
• DHS: Ransomware Attack Minimal in US, Did Not Hit Federal Govt