Officials across the globe scrambled over the weekend to catch the culprits behind a massive ransomware worm that disrupted operations at car factories, hospitals, shops and schools, while Microsoft on Sunday pinned blame on the US government for not disclosing more software vulnerabilities.
Cyber security experts said the spread of the worm dubbed WannaCry – "ransomware" that locked up more than 200,000 computers in more than 150 countries – had slowed but that the respite might only be brief amid fears new versions of the worm will strike.
In a blog post on Sunday, Microsoft president Brad Smith appeared to tacitly acknowledge what researchers had already widely concluded: the ransomware attack leveraged a hacking tool, built by the US National Security Agency, that leaked online in April.
The ransomware attack leveraged a hacking tool, built by the US National Security Agency
"This is an emerging pattern in 2017," Smith wrote. "We have seen vulnerabilities stored by the CIA show up on WikiLeaks, and now this vulnerability stolen from the NSA has affected customers around the world."
He also poured fuel on a long-running debate over how government intelligence services should balance their desire to keep software flaws secret – in order to conduct espionage and cyber warfare – against sharing those flaws with technology companies to better secure the internet.
"This attack provides yet another example of why the stockpiling of vulnerabilities by governments is such a problem," Smith wrote. He added that governments around the world should "treat this attack as a wake-up call" and "consider the damage to civilians that comes from hoarding these vulnerabilities and the use of these exploits."
The NSA and White House did not immediately respond to requests for comment about the Microsoft statement.
Economic experts offered differing views on how much the attack, and associated computer outages, would cost businesses and governments.
The non-profit US Cyber Consequences Unit research institute estimated that total losses would range in the hundreds of millions of dollars, but not exceed $1 billion. California-based cyber risk modelling firm Cyence put the total economic damage at $4 billion, citing costs associated with businesses interruption.
Today was expected to be a busy day, especially in Asia, which may not have seen the worst of the impact yet, as companies and organisations turned on their computers.
"Expect to hear a lot more about this [today] when users are back in their offices and might fall for phishing emails" or other as yet unconfirmed ways the worm may propagate, said Christian Karam, a Singapore-based security researcher.
Account addresses hard-coded into the malicious WannaCry virus appear to show the attackers had received just under $32,500 in anonymous bitcoin currency as of Sunday morning, but that amount could rise as more victims rush to pay ransoms of $300 or more.
The threat receded over the weekend after a British-based researcher, who declined to give his name but tweets under the profile @MalwareTechBlog, said he stumbled on a way to at least temporarily limit the worm's spread by registering a web address to which he noticed the malware was trying to connect.
Security experts said his move bought precious time for organisations seeking to block the attacks. (Reuters)