{"id":"CVE-2021-21284","state":"PUBLISHED","title":"privilege escalation in Moby","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. 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