UBUNTU-CVE-2021-40153

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    UBUNTU-CVE-2021-40153

    Published: 27 Aug 2021Last Modified: 5 Feb 2026
    Upstream:
    CVE-2021-40153

    Summary:

    Details: squashfs_opendir in unsquash-1.c in Squashfs-Tools 4.5 stores the filename in the directory entry; this is then used by unsquashfs to create the new file during the unsquash. The filename is not validated for traversal outside of the destination directory, and thus allows writing to locations outside of the destination.

    References: https://ubuntu.com/security/CVE-2021-40153, https://bugs.launchpad.net/ubuntu/+source/squashfs-tools/+bug/1941790, https://github.com/plougher/squashfs-tools/commit/79b5a555058eef4e1e7ff220c344d39f8cd09646, https://github.com/plougher/squashfs-tools/issues/72, https://github.com/plougher/squashfs-tools/commit/79b5a555058eef4e1e7ff220c344d39f8cd09646, https://ubuntu.com/security/notices/USN-5057-1, https://ubuntu.com/security/notices/USN-5078-2, https://www.cve.org/CVERecord?id=CVE-2021-40153

    Affected packages

    Package

    Name: squashfs-tools

    Purl: pkg:deb/ubuntu/squashfs-tools@1:4.3-3ubuntu2.16.04.3+esm1?arch=source&distro=esm-infra/xenial

    Affected ranges

    Type: ECOSYSTEM

    Events:

    Introduced- 0
    Fixed -1:4.3-3ubuntu2.16.04.3+esm1

    Affected versions

    1:4.2+20130409-2.1

    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-2021-40153 | CVE-DB