CVE-2021-21284
Publication date 2 February 2021
Last updated 24 July 2024
Ubuntu priority
Cvss 3 Severity Score
In Docker before versions 9.03.15, 20.10.3 there is a vulnerability involving the --userns-remap option in which access to remapped root allows privilege escalation to real root. When using "--userns-remap", if the root user in the remapped namespace has access to the host filesystem they can modify files under "/var/lib/docker/<remapping>" that cause writing files with extended privileges. Versions 20.10.3 and 19.03.15 contain patches that prevent privilege escalation from remapped user.
Status
Package | Ubuntu Release | Status |
---|---|---|
docker.io | 24.10 oracular |
Not affected
|
24.04 LTS noble |
Not affected
|
|
22.04 LTS jammy |
Not affected
|
|
20.04 LTS focal |
Fixed 20.10.7-0ubuntu1~20.04.1
|
|
18.04 LTS bionic |
Fixed 20.10.7-0ubuntu1~18.04.1
|
|
16.04 LTS xenial |
Vulnerable
|
|
14.04 LTS trusty | Not in release |
Severity score breakdown
Parameter | Value |
---|---|
Base score | 6.8 · Medium |
Attack vector | Adjacent |
Attack complexity | Low |
Privileges required | Low |
User interaction | None |
Scope | Changed |
Confidentiality | None |
Integrity impact | High |
Availability impact | None |
Vector | CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:N |
References
Other references
- https://github.com/moby/moby/security/advisories/GHSA-7452-xqpj-6rpc
- https://docs.docker.com/engine/release-notes/#20103
- https://github.com/moby/moby/commit/64bd4485b3a66a597c02c95f5776395e540b2c7c
- https://github.com/moby/moby/releases/tag/v19.03.15
- https://github.com/moby/moby/releases/tag/v20.10.3
- https://www.cve.org/CVERecord?id=CVE-2021-21284