The difference between the earlier WannaCry attacks and the latest one is a worm-like component that infects other computers by exploiting a critical remote code execution vulnerability in the Windows implementation of the Server Message Block 1.0 (SMBv1) protocol.
Europol chief Rob Wainwright said computer systems in more than 150 countries were hit, with the majority of organisations affected over the weekend in Europe.
"The governments of the world should treat this attack as a wake up call".
The Telegraph suggested that 90 percent of NHS trusts were using a 16 year old version of Windows XP which was particularly vulnerable to the attack.
Smith and others have long advocated that the world's governments need to pledge not to engage in cyberattacks that target civilian infrastructure. Just such a stockpiled flaw was behind the rapaciousness and rapidity with which the WannaCry ransomware spread.
A hacking group called Shadow Brokers released the malware in April, claiming to have discovered the flaw from the NSA, Kaspersky said.
"The EternalBlue exploit is part of a bigger leak called "Lost In Translation" that packs multiple vulnerabilities ranging from simple annoyances to extremely severe ones", Bogdan Botezatu, senior e-threat analyst at Bitdefender, said by email.
On Friday, the Kaspersky Lab company registered about 45,000 ransomware attacks in 74 countries worldwide, with the largest number of targets located in Russian Federation. Instead of having to develop their own arsenals of cyberweapons, they simply had to repurpose work done by the highly skilled cyber experts at the NSA, said Phillip Hallam-Baker, principal scientist at the cybersecurity firm Comodo.
Investors treated the attack as a buying opportunity for security stocks rather than a cause for concern over the risk it posed to companies, with the pan-European STOXX 600 .STOXX index little changed and major US indices up in midday trading.
"Whether or not you think the US government should be spending a fortune developing such cyberweapons, surely it is obvious that the weapons they develop should be properly secured. The CIA and NSA have been breached on a massive scale, and now the effects are being felt", Hallam-Baker said.
Some major technology companies, including Alphabet Inc's Google and Facebook Inc, declined comment on the Microsoft statement.
"Unfortunately the world is still very reactive to these attacks, looking for patches and fixes as opposed to preventive measures", said Campling.
"This attack provides yet another example of why the stockpiling of vulnerabilities by governments is such a problem", according to Smith.
"This is an emerging pattern in 2017".
Even before the WannaCrypt disaster, Smith said he and his colleagues had already seen vulnerabilities stored by the Central Intelligence Agency show up on WikiLeaks. "Repeatedly, exploits in the hands of governments have leaked into the public domain and caused widespread damage", he said.
Smith is urging world leaders need to consider following the "same rules applied to weapons in the physical world" for Internet vulnerabilities.