On 12 May 2017, there was a global wide-spread infections of a ransomware known as "WannaCry" aka. WanaCrypt0r. This ransomware has the capability to spread over the network by scanning for vulnerable systems, and infecting them. It then encrypts files on the system, and exhorts a ransom payment.
Please click on the following link below for the advisory from the Cyber Security Agency of Singapore, or contact email@example.com if you want to find out more about cybersecurity measures.