CVE-2020-3966: 
NixOS vulnerability analysis and mitigation

CVE-2020-3966 is a heap-overflow vulnerability due to a race condition issue in the USB 2.0 controller (EHCI) affecting VMware ESXi (versions 7.0, 6.7, and 6.5), Workstation (15.x), and Fusion (11.x). The vulnerability was disclosed on June 22, 2020, and VMware has evaluated its severity as Important with a CVSSv3 base score of 8.1 (VMware Advisory).

The vulnerability exists within the EHCI (USB 2.0 controller) component and results from a heap-overflow condition caused by a race condition. The issue has been assigned a CVSSv3 score of 8.1 with the following vector: AV:L/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H, indicating local access requirements with high attack complexity (ZDI Advisory).

A successful exploitation of this vulnerability could allow an attacker to execute code on the hypervisor from a virtual machine, potentially compromising the security of the host system. However, additional conditions beyond the attacker's control must be present for exploitation to be possible (VMware Advisory).

The vulnerability requires local access to a virtual machine for exploitation. While the vulnerability has been publicly disclosed, additional conditions beyond the attacker's control must be present for successful exploitation (VMware Advisory).

VMware has released patches for affected products: ESXi 7.0 (ESXi_7.0.0-1.20.16321839), ESXi 6.7 (ESXi670-202004101-SG), ESXi 6.5 (ESXi650-202005401-SG), Fusion 11.x (11.5.2), and Workstation 15.x (15.5.2). As a workaround, administrators can remove the USB Controller from affected virtual machines (VMware Advisory).