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
Status
| Package | Release | Status |
|---|---|---|
|
grub2 Launchpad, Ubuntu, Debian |
bionic |
Not vulnerable
(does not affect Secure Boot)
|
| focal |
Not vulnerable
(does not affect Secure Boot)
|
|
| impish |
Ignored
(end of life)
|
|
| jammy |
Not vulnerable
(does not affect Secure Boot)
|
|
| kinetic |
Not vulnerable
(does not affect Secure Boot)
|
|
| lunar |
Not vulnerable
(does not affect Secure Boot)
|
|
| mantic |
Not vulnerable
(does not affect Secure Boot)
|
|
| trusty |
Not vulnerable
(does not affect Secure Boot)
|
|
| upstream |
Needs triage
|
|
| xenial |
Not vulnerable
(does not affect Secure Boot)
|
|
|
grub2-signed Launchpad, Ubuntu, Debian |
bionic |
Released
(1.187.3~18.04.1)
|
| focal |
Released
(1.187.3~20.04.1)
|
|
| jammy |
Released
(1.187.3~22.04.1)
|
|
| kinetic |
Ignored
(end of life)
|
|
| lunar |
Not vulnerable
(1.192)
|
|
| mantic |
Not vulnerable
(1.193)
|
|
| trusty |
Needed
|
|
| upstream |
Needs triage
|
|
| xenial |
Needed
|
|
|
grub2-unsigned Launchpad, Ubuntu, Debian |
bionic |
Released
(2.06-2ubuntu14.1)
|
| focal |
Released
(2.06-2ubuntu14.1)
|
|
| jammy |
Released
(2.06-2ubuntu14.1)
|
|
| kinetic |
Ignored
(end of life)
|
|
| lunar |
Not vulnerable
(2.06-2ubuntu16)
|
|
| mantic |
Not vulnerable
(2.06-2ubuntu17)
|
|
| trusty |
Does not exist
|
|
| upstream |
Needs triage
|
|
| xenial |
Needed
|
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 |