Specifically, the vulnerability in the Remote Desktop Services could allow malware to spread across computers without the need for user device login. Exploits affect Windows 7, Windows Server 2008 R2, and older Windows versions.
Although no longer officially supported, Microsoft has also issued a security patch for these older versions including Windows XP and Windows Server 2003.
The company emphasizes they haven't detected any exploits prior to the patch release, but another scenario could be that attackers behind the malware utilize security vulnerabilities. Some systems equipped with Network Level Authentication will be particularly protected as they require authentication before the vulnerability can be exploited.
With its devastating impact and rapid spread, WannaCry became the largest ransomware cyberattack in history, hence Microsoft's release of patches to prevent these attacks is understandable.
Most malware like WannaCry tends to spread across devices of businesses, organizations unwilling to update their systems and disrupt crucial software. Therefore, these bug fixes are only effective if Microsoft can convince its customers.
To safeguard data on our computers, each of us needs to proactively install modern antivirus software such as Kaspersky Internet Security (KIS) or BKAV to ensure 24/7 system protection.
Currently, there is information suggesting that Facebook is about to restore the View As Public feature, meaning users can view their own profiles as another user. For more details, please read the article Facebook restores View As Public feature here.