In an interview on ABC's "This Week", Clapper said the worry was "this ransomware attack will be even larger" as people return to their desks after the weekend. A top Russian mobile operator said Friday it had come under cyberattacks that appeared similar to those that have crippled some United Kingdom hospitals.
British cybersecurity expert Graham Cluley doesn't want to blame the NSA for the attack. He noted that Europol is working with the Federal Bureau of Investigation to try and discover the people behind the attack. In a networked world where computer applications control business processes and databases in diverse fields like banking, telecom, and media, cyber attacks have the potential to throw life out of gear. "It's a big priority of mine that we protect the financial infrastructure", he said.
The WannaCry ransomware appears to only attack unpatched computers running Windows. The exploit was leaked last month as part of a trove of NSA spy tools.
As per the advisory issued by CERT-In, the ransomware infects other computers on the same network and is also spreading through malicious attachments to e-mails.
First, there was a highly unsafe security hole in Microsoft Windows, which became known after hackers leaked tools that were apparently created by the U.S. National Security Agency to exploit the hole. Machines that contained the patch are much less at risk than those that didn't.
Wannacry encrypts the files on infected Windows system and spreads by exploiting vulnerabilities, it said.
Though the ransomware continued to spread at a more subdued pace on Monday, many companies and government agencies were still struggling to recover from the first attack. The ransomware often scrambles filenames and changes their extension.
Britain's National Health Service said about a fifth of NHS trusts - the regional bodies that run hospitals and clinics - were hit by the attack on Friday, leading to thousands of canceled appointments and operations.
Russia's central bank said Saturday that no incidents had "compromising the data resources" of Russian banks, state news agency Tass reported.
"Global internet security has reached a moment of emergency", Qihoo360 warned.
That move, which cost just $10.69, redirected the attacks to the server of Kryptos Logic, the security company where he works.
FedEx: The company said this weekend it was "experiencing interference with some of our Windows-based systems caused by malware" and was trying to fix the problems as quickly as possible.
The computer can be infected by taking advantage of a Windows vulnerability that Microsoft (MSFT, Tech30) released a security patch for in March and computers that hadn't updated were still at risk.
But there will be other vulnerabilities to come, and not all of them will have fixes for older systems.
The NCA says: "Victims of fraud should report it to Action Fraud".
Start by removing the network connection (either remove the network cable or shut down your computer's wireless function) from your computer to prevent the spread of WannaCry.
Microsoft declined a request for an interview, but a statement on the company's blog said: "Seeing businesses and individuals affected by cyberattacks, such as the ones reported today, was painful".
Ransomware spreads easily when it encounters unpatched or outdated software. Here's how to turn automatic updates on.