Security experts find clues to ransomware worm's lingering risks

He said that private sector companies in the city were regularly hit by ransomware virus attacks in the last five years and that around 70 percent of them were infected.

The researchers warned that their solution would only work in certain conditions, namely if computers had not been rebooted since becoming infected and if victims applied the fix before WannaCry carried out its threat to lock their files permanently.

The researchers - Adrien Guinet, Matthieu Suiche and Benjamin Delpy - worked separately. The virus essentially encrypted files of the affected computer, demanding the user payment of $300 in bitcoin to regain access to these files.

It also added that the top five cities impacted by the ransomware attack are Kolkata followed by Delhi, Bhubaneswar, Pune and Mumbai, while the top top five states with the largest number of reports of WannaCry malware are West Bengal, Maharashtra, Gujarat, Delhi NCR, and Odisha.

The fight against cyberattacks has sparked exponential growth in global protection spending, with the cyber security market estimated at $120 billion this year, more than 30 times its size just over a decade ago. Right-click the file in your Downloads folder and select "Extract all".

Adrien Guinet, who works for a Paris-based firm called Quarkslab, says however that the tool is not ideal and only works if the infected computers have not been rebooted after being hit by the program. Guinet exploited a flaw in older versions of Windows to retrieve WannaCry's encryption key from a PC's memory.

On Friday, the central bank said it had sent recommendations to Russian banks on updating their Windows software in April, before the Wannacry attack it said it had recorded on May 12. This is where a person's luck comes into the picture, he should hope that the associated memory isn't reallocated and erased so that the prime numbers belonging to the key can be recovered.

In general, you should be creating a copy of your data in the first place, in case your computer fails or is lost.

In most cases, a new version of Windows or another operating system would also need a new computer that was powerful enough to run it, and potentially new bespoke hardware and software to enable the organisation to do its job. And, it turns out, for all the hype surrounding your grandpa's taste in operating systems, it wasn't Windows XP that was the problem. However, the flaw that the decryption tools exploit was fixed in Windows 8 and later.

Yet, according to Smith, all Windows computers that are fully updated are safe from the attack and Microsoft has since issued Customer Guidance for WannaCrypt attacks and a fix for versions of Windows it had previously "retired" including Windows XP.

A French researcher has released a software tool that he claims can restore some of the computers infected by the WannaCry ransomware.

  • Carolyn Briggs