I was researching and found an article on cnet entitled Microsoft patches 19-year-old Windows bug. In this article it details that IBM discovered it in May this year. IT also said
“The Windows bug, dubbed WinShock, could be used to remotely run code on a computer if the user views a malicious webpage via Internet Explorer. Once a machine would be infected, the attacker could control it remotely. The flaw affected every version of Microsoft’s desktop OS since Windows 95.”
I think that the crackers (people who use hacking skills to do illegal things), and virus developers knew about and exploited the WinShock bug. This is why for all people who use windows (or any other os) it is a good idea to apply the security fixes and updates when they are available as they fix bugs like this that are found.Microsoft bug finally packed.