Resource Exhaustion Vulnerability in Linux Kernel with Unprivileged User Namespaces

CVE-2019-20794 · MEDIUM Severity

CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H

An issue was discovered in the Linux kernel 4.18 through 5.6.11 when unprivileged user namespaces are allowed. A user can create their own PID namespace, and mount a FUSE filesystem. Upon interaction with this FUSE filesystem, if the userspace component is terminated via a kill of the PID namespace's pid 1, it will result in a hung task, and resources being permanently locked up until system reboot. This can result in resource exhaustion.

Learn more about our Cis Benchmark Audit For Distribution Independent Linux.