privilege escalation in Moby
CVE-2021-21284
6.8MEDIUM
What is 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. 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/" that cause writing files with extended privileges. Versions 20.10.3 and 19.03.15 contain patches that prevent privilege escalation from remapped user.
Affected Version(s)
moby < 19.03.15 < 19.03.15
moby >= 20.0.0, < 20.10.3 < 20.0.0, 20.10.3