"Vaccine, not Killswitch, Found for Petya (NotPetya) Ransomware Outbreak"

Amit Serper, a security researcher at Cybereason, has developed a vaccine to prevent the infection of the Petya ransomware on a computer. Though the method presented does not act as a kill switch to stop the global spread of this ransomware, it does stop the ransomware from executing on an individual computer. Serper discovered that the Petya ransomware ceases its encryption process if a certain local file already exists on the disk, therefore the creation and setting of this file to read-only would halt the execution of the ransomware. This article further discusses the reasoning behind the various names of this ransomware along with how to enable the vaccine on a computer. 

Bleeping Computer reports "Vaccine, not Killswitch, Found for Petya (NotPetya) Ransomware Outbreak"