CVE-2021-33656: When setting font with malicous data by ioctl cmd PIO_FONT,kernel will write memory out of bounds

Medium severity · published Jul 18, 2022

CVE-2021-33656

When setting font with malicous data by ioctl cmd PIO_FONT,kernel will write memory out of bounds

6.8

CVSS

0.6%

EPSS

On KEV

Description

When setting font with malicous data by ioctl cmd PIO_FONT,kernel will write memory out of bounds.

CVSS vector

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

Attack vector

Physical

Complexity

Low

Privileges

None

User interaction

None

Confidentiality

High

Integrity

High

Availability

High

Scope

Unchanged

Exploitation

Is it being used?

Exploit prediction (EPSS)0.6% · higher than 49% of CVEs

Exploited in the wildNo evidence yet

CISA KEVNot listed

Ransomware campaign useNot known

Affected products

Which versions

Kernel · Linux

before 5.10.127 · source: NVD

openEuler:kernel ·

<5.10.127 · source: vendor

Debian Linux · Debian

10.0 · source: NVD

Openeuler · Openatom

20.03; 20.03; 20.03 · source: NVD

Affected product

Kernel

Linux

All Kernel CVEs

References

NVD

https://nvd.nist.gov/vuln/detail/CVE-2021-33656

CVE.org

https://www.cve.org/CVERecord?id=CVE-2021-33656

Mailing List

http://www.openwall.com/lists/oss-security/2022/07/19/3

Patch

https://git.kernel.org/pub/scm/linux/kernel/git/stable/stable-queue.git/tree/releases/5.10.127/vt-drop-old-font-ioctls.patch

Mailing List

https://lists.debian.org/debian-lts-announce/2022/10/msg00000.html

Third Party Advisory

https://www.openeuler.org/en/security/cve/detail.html?id=CVE-2021-33656&packageName=kernel