CVE-2021-21284
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.
Does this matter?
Lower severity and a low EPSS score (1.06%). Track it; it rarely justifies an emergency change on its own.
Description
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.
- CVSS 3.1
- 6.8 MEDIUMCVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:N
- EPSS
- 1.06% probability · 63th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-22
- Affected
- docker/docker · debian/debian linux · netapp/e-series santricity os controller
- Source
- security-advisories@github.com
References
- https://docs.docker.com/engine/release-notes/#20103Release Notes, Vendor Advisory
- https://github.com/moby/moby/commit/64bd4485b3a66a597c02c95f5776395e540b2c7cPatch, Third Party Advisory
- https://github.com/moby/moby/releases/tag/v19.03.15Release Notes, Third Party Advisory
- https://github.com/moby/moby/releases/tag/v20.10.3Release Notes, Third Party Advisory
- https://github.com/moby/moby/security/advisories/GHSA-7452-xqpj-6rpcThird Party Advisory
- https://security.gentoo.org/glsa/202107-23Patch, Third Party Advisory
- https://security.netapp.com/advisory/ntap-20210226-0005/Third Party Advisory
- https://www.debian.org/security/2021/dsa-4865Third Party Advisory
- https://docs.docker.com/engine/release-notes/#20103Release Notes, Vendor Advisory
- https://github.com/moby/moby/commit/64bd4485b3a66a597c02c95f5776395e540b2c7cPatch, Third Party Advisory
- https://github.com/moby/moby/releases/tag/v19.03.15Release Notes, Third Party Advisory
- https://github.com/moby/moby/releases/tag/v20.10.3Release Notes, Third Party Advisory
- https://github.com/moby/moby/security/advisories/GHSA-7452-xqpj-6rpcThird Party Advisory
- https://security.gentoo.org/glsa/202107-23Patch, Third Party Advisory
- https://security.netapp.com/advisory/ntap-20210226-0005/Third Party Advisory
- https://www.debian.org/security/2021/dsa-4865Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.