CVE-2021-3697
Publication date 6 July 2022
Last updated 18 August 2025
Ubuntu priority
Description
A crafted JPEG image may lead the JPEG reader to underflow its data pointer, allowing user-controlled data to be written in heap. To a successful to be performed the attacker needs to perform some triage over the heap layout and craft an image with a malicious format and payload. This vulnerability can lead to data corruption and eventual code execution or secure boot circumvention. This flaw affects grub2 versions prior grub-2.12.
Status
| Package | Ubuntu Release | Status |
|---|---|---|
| grub2 | 25.10 questing |
Not affected
|
| 25.04 plucky |
Not affected
|
|
| 24.04 LTS noble |
Not affected
|
|
| 22.04 LTS jammy |
Not affected
|
|
| 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
|
|
| 24.04 LTS noble |
Not affected
|
|
| 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
|
|
| 24.04 LTS noble |
Not affected
|
|
| 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 |
Vulnerable
|
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score |
7.0 · High
|
| Attack vector | Local |
| Attack complexity | High |
| Privileges required | Low |
| User interaction | None |
| Scope | Unchanged |
| Confidentiality | High |
| Integrity impact | High |
| Availability impact | High |
| Vector | CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H |
References
Related Ubuntu Security Notices (USN)
- USN-6355-1
- GRUB2 vulnerabilities
- 8 September 2023