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.
The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.
| Link | Tags |
|---|---|
| https://docs.docker.com/engine/release-notes/#20103 | release notes vendor advisory |
| https://github.com/moby/moby/releases/tag/v20.10.3 | third party advisory release notes |
| https://github.com/moby/moby/releases/tag/v19.03.15 | third party advisory release notes |
| https://github.com/moby/moby/security/advisories/GHSA-7452-xqpj-6rpc | third party advisory |
| https://github.com/moby/moby/commit/64bd4485b3a66a597c02c95f5776395e540b2c7c | third party advisory patch |
| https://security.netapp.com/advisory/ntap-20210226-0005/ | third party advisory |
| https://www.debian.org/security/2021/dsa-4865 | third party advisory vendor advisory |
| https://security.gentoo.org/glsa/202107-23 | patch vendor advisory third party advisory |