Thanks to Kaspersky, we now know that 98% of the Windows machines infected by WannaCry/WannaCrypt were running Windows 7. Since, once it gets a foothold, the malware can infect an entire network, most of the attention was focused on LAN based attacks. My previous blog was about using the Windows firewall as a defensive measure.
But any malware can spread in multiple ways so there is always a need for anti-malware software on Windows PCs. The May 12th blog post, Customer Guidance for WannaCrypt attacks, in which Microsoft announced the release of a bug fix for Windows XP, mentioned that