Your submission was sent successfully! Close

You have successfully unsubscribed! Close

CVE-2021-3695

Published: 6 July 2022

A crafted 16-bit grayscale PNG image may lead to a out-of-bounds write in the heap area. An attacker may take advantage of that to cause heap data corruption or eventually arbitrary code execution and circumvent secure boot protections. This issue has a high complexity to be exploited as an attacker needs to perform some triage over the heap layout to achieve signifcant results, also the values written into the memory are repeated three times in a row making difficult to produce valid payloads. This flaw affects grub2 versions prior grub-2.12.

Priority

Medium

Cvss 3 Severity Score

4.5

Score breakdown

Status

Package Release Status
grub2
Launchpad, Ubuntu, Debian
bionic Needed

focal Needed

jammy Needed

upstream Needs triage

kinetic Not vulnerable
(2.06-2ubuntu12)
xenial Needed

impish Ignored
(end of life)
lunar Not vulnerable
(2.06-2ubuntu16)
grub2-unsigned
Launchpad, Ubuntu, Debian
jammy Pending
(2.06-2ubuntu14.1)
upstream Needs triage

lunar Not vulnerable
(2.06-2ubuntu16)
xenial Needed

trusty Does not exist

bionic Pending
(2.06-2ubuntu14.1)
focal Pending
(2.06-2ubuntu14.1)
kinetic Ignored
(end of life)
grub2-signed
Launchpad, Ubuntu, Debian
upstream Needs triage

bionic Pending
(1.187.3~18.04.1)
lunar Not vulnerable
(1.192)
trusty Needed

xenial Needed

focal Pending
(1.187.3~20.04.1)
jammy Pending
(1.187.3~22.04.1)
kinetic Ignored
(end of life)

Severity score breakdown

Parameter Value
Base score 4.5
Attack vector Local
Attack complexity High
Privileges required Low
User interaction None
Scope Unchanged
Confidentiality Low
Integrity impact Low
Availability impact Low
Vector CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L