{"id":"GHSA-7452-xqpj-6rpc","summary":"moby Access to remapped root allows privilege escalation to real root","details":"### Impact\n\nWhen 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/\u003cremapping\u003e` that cause writing files with extended privileges.\n\n### Patches\n\nVersions 20.10.3 and 19.03.15 contain patches that prevent privilege escalation from remapped user.\n\n### Credits\n\nMaintainers would like to thank Alex Chapman for discovering the vulnerability; @awprice, @nathanburrell, @raulgomis, @chris-walz, @erin-jensby, @bassmatt, @mark-adams, @dbaxa for working on it and Zac Ellis for responsibly disclosing it to security@docker.com","aliases":["CVE-2021-21284"],"modified":"2026-07-17T21:15:33.267180469Z","published":"2024-01-31T23:14:25Z","database_specific":{"nvd_published_at":"2021-02-02T18:15:00Z","cwe_ids":["CWE-22"],"severity":"MODERATE","github_reviewed":true,"github_reviewed_at":"2024-01-31T23:14:25Z"},"references":[{"type":"WEB","url":"https://github.com/moby/moby/security/advisories/GHSA-7452-xqpj-6rpc"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2021-21284"},{"type":"WEB","url":"https://github.com/moby/moby/commit/64bd4485b3a66a597c02c95f5776395e540b2c7c"},{"type":"WEB","url":"https://docs.docker.com/engine/release-notes/#20103"},{"type":"WEB","url":"https://github.com/moby/moby/releases/tag/v19.03.15"},{"type":"WEB","url":"https://github.com/moby/moby/releases/tag/v20.10.3"},{"type":"WEB","url":"https://security.gentoo.org/glsa/202107-23"},{"type":"WEB","url":"https://security.netapp.com/advisory/ntap-20210226-0005"},{"type":"WEB","url":"https://www.debian.org/security/2021/dsa-4865"}],"affected":[{"package":{"name":"github.com/moby/moby","ecosystem":"Go","purl":"pkg:golang/github.com/moby/moby"},"ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"19.3.15"}]}],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2024/01/GHSA-7452-xqpj-6rpc/GHSA-7452-xqpj-6rpc.json"}},{"package":{"name":"github.com/moby/moby","ecosystem":"Go","purl":"pkg:golang/github.com/moby/moby"},"ranges":[{"type":"SEMVER","events":[{"introduced":"20.10.0-beta1"},{"fixed":"20.10.3"}]}],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2024/01/GHSA-7452-xqpj-6rpc/GHSA-7452-xqpj-6rpc.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:N"}]}