UK cyber-security firm Sophos reported detecting a spike in ransomware attacks at the end of last week from a new strain named MegaCortex. MegaCortex now joins an ever-growing list of ransomware strains that cyber-criminal groups are using only in targeted attacks, rather than with spam or other mass deployment techniques. Since then, the number of attacks has been growing, but they spiked mid last week when Sophos says it detected 47 attacks --accounting for two-thirds of all the 76 MegaCortex attacks the company has seen all year. While Sophos was not able to pinpoint with certainty how MegaCortex got on infected hosts, several cyber-security researchers tweeted over the weekend that the ransomware appears to be dropped on attacked networks via a malware loader named Rietspoof. But despite the delivery method, MegaCortex appears to be just as dangerous as the other "big-game hunting" ransomware strains, with hackers quickly escalating their access to a domain controller, from where they try to deploy the ransomware to as many internal workstations as possible.