However, new research from cyber security firm Kaspersky has revealed that computers running Windows 7 were hardest hit by the ransomware attack, accounting for a staggering 98 percent of infected computers.
A statement from Microsoft president Brad Smith said: "As cybercriminals become more sophisticated, there is simply no way for customers to protect themselves against threats unless they update their systems".
In a survey for Reuters, BitSight found that 67 per cent of infected PCs it infected were running Windows 7, despite the OS being installed on fewer than half of Windows PCs worldwide. This is probably what happened at Microsoft this week, with older versions of Windows being widely affected by a new and nasty ransomware named WannaCry, or WannaCrypt.
For computers within corporate networks, once an attack is spotted, disconnection of the invaded computer from the Internet and internal networks needs to be done immediately. There have been no reports that anyone who paid has had their data restored by those behind the attack.
Microsoft has since said that Windows 10 is the version of its operating system that gives the best protection from Wanna Cry - and the data released from Kaspersky would also confirm this.More news: Diane Abbott cancels radio appearance after embarrassing Sky News interview
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"The exploit technique is known as HeapSpraying and is used to inject shellcode into vulnerable systems allowing for the exploitation of the system", the firm said in an advisory. This could potentially lead to more hacks like the WannaCry Ransomware.
Last week, developer Adrien Guinet discovered that a handy vulnerability in Windows' file encryption subsystem was not properly removing the private key used for the encryption from memory, and worked to turn that vulnerability into a tool capable of pulling the private key and transforming it into a format suitable for decrypting affected files without paying the ransom. Windows 10 represented 15 per cent of infections, while Windows 8, 8.1, Vista and XP made up the remainder. Worst hit - Windows 7 x64.
The reason behind the Windows 7 infection rates could have to do with a critical security patch issued in the spring of 2017 that some users may have missed.
2008 R2 Server clients accounted for more than 1% of infections.