The udl_fb_mmap function in drivers/gpu/drm/udl/udl_fb.c at the Linux kernel version 3.4 and up to and including 4.15 has an integer-overflow vulnerability allowing local users with access to the udldrmfb driver to obtain full read and write permissions on kernel physical pages, resulting in a code execution in kernel space.
https://patchwork.freedesktop.org/patch/211845/
https://www.debian.org/security/2018/dsa-4188
https://www.debian.org/security/2018/dsa-4187
https://lists.debian.org/debian-lts-announce/2018/05/msg00000.html
https://usn.ubuntu.com/3654-2/
https://usn.ubuntu.com/3654-1/
https://usn.ubuntu.com/3656-1/
https://usn.ubuntu.com/3677-2/
https://usn.ubuntu.com/3677-1/
https://usn.ubuntu.com/3674-2/
https://usn.ubuntu.com/3674-1/
https://research.checkpoint.com/mmap-vulnerabilities-linux-kernel/
https://access.redhat.com/errata/RHSA-2018:3096
Source: MITRE
Published: 2018-04-23
Updated: 2023-03-03
Type: CWE-190
Base Score: 7.2
Vector: AV:L/AC:L/Au:N/C:C/I:C/A:C
Impact Score: 10
Exploitability Score: 3.9
Severity: HIGH
Base Score: 7.8
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Impact Score: 5.9
Exploitability Score: 1.8
Severity: HIGH