CVE-2022-28736

Publication date 20 July 2023

Last updated 18 August 2025

Ubuntu priority

Medium

Why this priority?

Cvss 3 Severity Score

6.4 · Medium

Score breakdown

Description

There’s a use-after-free vulnerability in grub_cmd_chainloader() function; The chainloader command is used to boot up operating systems that doesn’t support multiboot and do not have direct support from GRUB2. When executing chainloader more than once a use-after-free vulnerability is triggered. If an attacker can control the GRUB2’s memory allocation pattern sensitive data may be exposed and arbitrary code execution can be achieved.

Status

Package Ubuntu Release Status
grub2 25.10 questing
Not affected
25.04 plucky
Not affected
24.10 oracular
Not affected
24.04 LTS noble
Not affected
23.10 mantic
Not affected
23.04 lunar
Not affected
22.10 kinetic
Not affected
22.04 LTS jammy
Not affected
21.10 impish Ignored end of life
20.04 LTS focal
Not affected
18.04 LTS bionic
Not affected
16.04 LTS xenial
Not affected
14.04 LTS trusty
Not affected
grub2-unsigned 25.10 questing
Not affected
25.04 plucky
Not affected
24.10 oracular
Not affected
24.04 LTS noble
Not affected
23.10 mantic
Not affected
23.04 lunar
Not affected
22.10 kinetic Ignored end of life
22.04 LTS jammy
Fixed 2.06-2ubuntu14.1
20.04 LTS focal
Fixed 2.06-2ubuntu14.1
18.04 LTS bionic
Fixed 2.06-2ubuntu14.1
16.04 LTS xenial
Vulnerable
14.04 LTS trusty Not in release
grub2-signed 25.10 questing
Not affected
25.04 plucky
Not affected
24.10 oracular
Not affected
24.04 LTS noble
Not affected
23.10 mantic
Not affected
23.04 lunar
Not affected
22.10 kinetic Ignored end of life
22.04 LTS jammy
Fixed 1.187.3~22.04.1
20.04 LTS focal
Fixed 1.187.3~20.04.1
18.04 LTS bionic
Fixed 1.187.3~18.04.1
16.04 LTS xenial
Vulnerable
14.04 LTS trusty
Needs evaluation

Severity score breakdown

Parameter Value
Base score 6.4 · Medium
Attack vector Local
Attack complexity High
Privileges required High
User interaction None
Scope Unchanged
Confidentiality High
Integrity impact High
Availability impact High
Vector CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H

References

Related Ubuntu Security Notices (USN)

    • USN-6355-1
    • GRUB2 vulnerabilities
    • 8 September 2023

Other references