An explosion of cyberattacks is infecting servers around the world with crippling ransomware by exploiting a vulnerability that was patched two years ago, it was widely reported on Monday.
The hacks exploit a flaw in ESXi, a hypervisor VMware sells to cloud hosts and other large-scale enterprises to consolidate their hardware resources. ESXi is what’s known as a bare-metal, or Type 1, hypervisor, meaning it’s essentially its own operating system that runs directly on server hardware. By contrast, servers running the more familiar Type 2 class of hypervisors, such as VMware’s VirtualBox, run as apps on top of a host operating system. The Type 2 hypervisors then run virtual machines that host their own guest OSes such as Windows, Linux or, less commonly, macOS.
Advisories published recently by computer emergency response teams (CERT) in France, Italy, and Austria report a “massive” campaign that began no later than Friday and has gained momentum since then. Citing results of a search on Census, CERT officials in Austria, said that as of Sunday, there were more than 3,200 infected servers, including eight in that country.