CVE-2021-20269
Publication date 10 March 2022
Last updated 25 August 2025
Ubuntu priority
Description
A flaw was found in the permissions of a log file created by kexec-tools. This flaw allows a local unprivileged user to read this file and leak kernel internal information from a previous panic. The highest threat from this vulnerability is to confidentiality. This flaw affects kexec-tools shipped by Fedora versions prior to 2.0.21-8 and RHEL versions prior to 2.0.20-47.
Status
| Package | Ubuntu Release | Status |
|---|---|---|
| kexec-tools | 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 in release |
Notes
sbeattie
on ubuntu/debian, makedumpfile from src:makedumpfile is used to create the dmesg file, and correctly limits the permissions on it. On Fedora/RedHat, the kdump-lib-initramfs.sh is used and is where the vulnerability lies. This script is not included in ubuntu/debian packaging.
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score |
5.5 · Medium
|
| Attack vector | Local |
| Attack complexity | Low |
| Privileges required | Low |
| User interaction | None |
| Scope | Unchanged |
| Confidentiality | High |
| Integrity impact | None |
| Availability impact | None |
| Vector | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N |