CVE-2021-3864

    Dashboard / Vulnerabilities / CVE-2021-3864

    CVE-2021-3864

    Published: 26 Aug 2022Last Modified: 14 Mar 2026

    Summary:

    Details: A flaw was found in the way the dumpable flag setting was handled when certain SUID binaries executed its descendants. The prerequisite is a SUID binary that sets real UID equal to effective UID, and real GID equal to effective GID. The descendant will then have a dumpable value set to 1. As a result, if the descendant process crashes and core_pattern is set to a relative value, its core dump is stored in the current directory with uid:gid permissions. An unprivileged local user with eligible root SUID binary could use this flaw to place core dumps into root-owned directories, potentially resulting in escalation of privileges.

    References: https://lore.kernel.org/all/20211221021744.864115-1-longman%40redhat.com/, https://lore.kernel.org/all/20211226150310.GA992%401wt.eu/, https://lore.kernel.org/lkml/20211228170910.623156-1-wander%40redhat.com/, https://access.redhat.com/security/cve/CVE-2021-3864, https://security-tracker.debian.org/tracker/CVE-2021-3864, https://bugzilla.redhat.com/show_bug.cgi?id=2015046, https://www.openwall.com/lists/oss-security/2021/10/20/2

    Affected packages

    Package

    Name:

    Purl:

    Affected ranges

    Type: N/A

    Events:

    Introduced- None
    Fixed -None

    Affected versions

    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
    CVE-2021-3864 | CVE-DB