Petya Ransomware: There is No Guarantee That Paying Ransom Will Unlock Files

The rapid pace of the new Petya ransomware attack points at another worm that can spread from computer to computer by itself, Mimecast has said. In an advisory, Steven Malone, director of security product management at Mimecast, commented, “Many commentators think WannaCry came from hackers in Russia, perhaps as an experiment that escaped early. Therefore it’s not too surprising that Ukraine’s critical national infrastructure has been crippled today while other firms in Europe may have been hit in the crossfire.”

Malone added that as with the early stages of the Wannacry outbreak, the bitcoin wallet associated with this ransomware is not seeing high volumes of payments. “Six people globally have currently paid the ransom, suggesting this won’t be a financially-successful attack. A cyber resilience strategy that acknowledges that attacks are likely to continue and will sometimes be successful is required. Defence-in-depth security and continuity plans are needed to keep critical services running every time they are attacked,” Malone added.

According to Malone, this new outbreak once again highlights the disruptive power of ransomware like never before. “Simply by encrypting and blocking access to files, critical national services and valuable business data can be damaged,” he added.

Hence, Mimecast has advised organisations never to succumb to the pressure to pay the ransom to regain access to their applications and data. There is no guarantee this will unlock files and further motivates and finances attackers to expand their ransomware campaigns.

Email has traditionally been the primary attack route for ransomware. Attackers often send Microsoft Office documents with malicious macros that download and install malware. This includes Word, Excel, PowerPoint and also PDFs. Clever social engineering will trick employees into enabling the macros and delivering the ransomware payload.

Preventive measures alone can’t keep up with the fast-evolving nature of ransomware attacks and as this attack highlights, there are many ways for an infection to enter an organization. It’s vital you regularly backup critical data and ensure that ransomware cannot spread to backup files.  Ransomware can take time to encrypt large volumes of files, particularly across a network share. It is imperative to ensure your back-up window is long enough to go back before any infection begins.

“Backup and recovery measures only work after an attack, and cost organizations in downtime and IT resources dealing with the attack and aftermath. You must be able to continue to operate during the infection period and recover quickly once the infection has been removed,” concluded Malone.