UBUNTU-CVE-2021-41091

    Dashboard / Vulnerabilities / UBUNTU-CVE-2021-41091

    UBUNTU-CVE-2021-41091

    Published: 4 Oct 2021Last Modified: 24 Mar 2026
    Upstream:

    Summary:

    Details: Moby is an open-source project created by Docker to enable software containerization. A bug was found in Moby (Docker Engine) where the data directory (typically `/var/lib/docker`) contained subdirectories with insufficiently restricted permissions, allowing otherwise unprivileged Linux users to traverse directory contents and execute programs. When containers included executable programs with extended permission bits (such as `setuid`), unprivileged Linux users could discover and execute those programs. When the UID of an unprivileged Linux user on the host collided with the file owner or group inside a container, the unprivileged Linux user on the host could discover, read, and modify those files. This bug has been fixed in Moby (Docker Engine) 20.10.9. Users should update to this version as soon as possible. Running containers should be stopped and restarted for the permissions to be fixed. For users unable to upgrade limit access to the host to trusted users. Limit access to host volumes to trusted containers.

    Affected packages

    Package

    Name: docker.io

    Purl: pkg:deb/ubuntu/[email protected]~18.04.2?arch=source&distro=bionic

    Affected ranges

    Type: ECOSYSTEM

    Events:

    Introduced- 0
    Fixed -20.10.7-0ubuntu5~18.04.2

    Affected versions

    1.13.1-0ubuntu6

    Common Vulnerability Scoring System

    Attack Vector
    Network
    Adjacent
    Local
    Physical
    Privileges Required
    None
    Low
    High
    User Interaction
    None
    Required
    Scope
    Unchanged
    Changed
    Confidentiality
    None
    Low
    High
    Integrity
    None
    Low
    High
    Availability
    None
    Low
    High
    UBUNTU-CVE-2021-41091 | CVE-DB