The aufs module for the Linux kernel 3.x and 4.x does not properly restrict the mount namespace, which allows local users to gain privileges by mounting an aufs filesystem on top of a FUSE filesystem, and then executing a crafted setuid program.
Severity
CVSS 3.1
7.8 high
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS
0.9% chance of exploitation in the next 30 days; higher than 59% of CVEs (scores of 2026-10-31)