Identified by Positive Technologies security researcher Alexander Popov, the high severity bugs resided in the virtual socket implementation of the Linux kernel.

Tracked as CVE-2021-26708 and featuring a CVSS score of 7.0, the security holes were introduced in Linux kernel version 5.5 in November 2019.

The vulnerabilities are the result of race conditions that were added with virtual socket (VSOCK) multi-transport support, with all major GNU/Linux distributions impacted, as the vulnerable kernel drivers (CONFIG_VSOCKETS and CONFIG_VIRTIO_VSOCKETS) are shipped to all of them, as kernel modules.