The long story short. Widely used in a past exploit by NSA has been stolen and used as a back door to redistribute virus collecting money. This exploit has been used by NSA to do a full files backup w/o permission from the owner AKA ‘spy access’. Therefore, Microsoft patched this exploit 2 months ago for all supported version of the Windows (outdated software OSes like Windows XP and Windows server 2003 stays without patches at the start). Unfortunately, the UK government who spent £5.5m to extend support for Windows XP (mainly used by NHS) has finished 8 April last year. As a result, the virus attacked companies with outdated software. Moreover, the virus only needs one machine (unsupported or not updated OS) to gain access to the organisation’s local network. Finally, Microsoft released patches for unsupported OS versions and users can now download and install a patch to close an open window used by NSA.
Thank you Microsoft for making a costly Patch for usupoorted OS.
Patches for Windows XP, Windows Server 2003 and Windows 8 at:
https://blogs.technet.microsoft.com/msrc/2017/05/12/customer-guidance-fo…
Sources:
https://blogs.microsoft.com/on-the-issues/2017/05/14/need-urgent-collect…
https://techcrunch.com/2017/05/16/wannacrypt-raises-questions-over-gover…
http://www.computerweekly.com/news/2240217389/Government-signs-55m-Micro…
https://www.petri.com/dont-blame-microsoft-wannacrypt-vulnerability-expl…