Rapid7

vulnerability

Amazon Linux AMI 2: CVE-2021-21284: Security patch for docker (Multiple Advisories)

Severity
3
CVSS
(AV:A/AC:L/Au:S/C:N/I:P/A:N)
Published
Feb 2, 2021
Added
Jul 4, 2022
Modified
May 20, 2026

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.

Solutions

amazon-linux-ami-2-upgrade-dockeramazon-linux-ami-2-upgrade-docker-debuginfo
Title
Rapid7 Labs

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