CVSS2
Attack Vector
LOCAL
Attack Complexity
LOW
Authentication
NONE
Confidentiality Impact
PARTIAL
Integrity Impact
PARTIAL
Availability Impact
COMPLETE
AV:L/AC:L/Au:N/C:P/I:P/A:C
CVSS3
Attack Vector
PHYSICAL
Attack Complexity
LOW
Privileges Required
HIGH
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
LOW
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.1/AV:P/AC:L/PR:H/UI:N/S:U/C:L/I:H/A:H
EPSS
Percentile
5.1%
An out-of-bounds (OOB) memory access flaw was found in fbcon_get_font() in drivers/video/fbdev/core/fbcon.c in fbcon driver module in the Linux kernel. A bound check failure allows a local attacker with special user privilege to gain access to out-of-bounds memory, leading to a system crash or a leak of internal kernel information. The highest threat from this vulnerability is to integrity and system availability.
Add 'nomodeset' option as kernel boot parameter to disable frame buffering (edit /etc/default/grub, and run 'grub2-mkconfig -o /boot/grub2/grub.cfg' and reboot).
# cat /proc/cmdline
BOOT_IMAGE=(hd0,msdos1)/vmlinuz-4.18.0-147.el8.x86_64 root=/dev/mapper/rhel_rhel8u2--1-root ro crashkernel=auto resume=/dev/mapper/rhel_rhel8u2--1-swap rd.lvm.lv=rhel_rhel8u2-1/root rd.lvm.lv=rhel_rhel8u2-1/swap nomodeset
# ls -l /dev/fb*
ls: cannot access '/dev/fb*': No such file or directory
CVSS2
Attack Vector
LOCAL
Attack Complexity
LOW
Authentication
NONE
Confidentiality Impact
PARTIAL
Integrity Impact
PARTIAL
Availability Impact
COMPLETE
AV:L/AC:L/Au:N/C:P/I:P/A:C
CVSS3
Attack Vector
PHYSICAL
Attack Complexity
LOW
Privileges Required
HIGH
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
LOW
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.1/AV:P/AC:L/PR:H/UI:N/S:U/C:L/I:H/A:H
EPSS
Percentile
5.1%