UBUNTU-CVE-2021-26910

    Dashboard / Vulnerabilities / UBUNTU-CVE-2021-26910

    UBUNTU-CVE-2021-26910

    Published: 8 Feb 2021Last Modified: 4 Feb 2026
    Upstream:
    CVE-2021-26910
    Aliases:
    USN-5141-1

    Summary:

    Details: Firejail before 0.9.64.4 allows attackers to bypass intended access restrictions because there is a TOCTOU race condition between a stat operation and an OverlayFS mount operation.

    References: https://ubuntu.com/security/CVE-2021-26910, https://www.openwall.com/lists/oss-security/2021/02/08/5, https://unparalleled.eu/publications/2021/advisory-unpar-2021-0.txt, https://unparalleled.eu/blog/2021/20210208-rigged-race-against-firejail-for-local-root/, http://www.openwall.com/lists/oss-security/2021/02/09/1, https://github.com/netblue30/firejail/commit/97d8a03cad19501f017587cc4e47d8418273834b, https://github.com/netblue30/firejail/releases/tag/0.9.64.4, https://ubuntu.com/security/notices/USN-5141-1, https://www.cve.org/CVERecord?id=CVE-2021-26910

    Affected packages

    Package

    Name: firejail

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

    Affected ranges

    Type: ECOSYSTEM

    Events:

    Introduced- 0
    Fixed -None

    Affected versions

    0.9.28-1
    0.9.32-1
    0.9.34-1
    0.9.36-1
    0.9.38-1
    0.9.38-1ubuntu0.1
    0.9.38.10-0ubuntu0.16.04.1

    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-2021-26910 | CVE-DB