CVE Feed

    Dashboard / CVE / CVE-2021-3995

    CVE-2021-3995

    A logic error was found in the libmount library of util-linux in the function that allows an unprivileged user to unmount a FUSE filesystem. This flaw allows an unprivileged local attacker to unmount FUSE filesystems that belong to certain other users who have a UID that is a prefix of the UID of the attacker in its string form. An attacker may use this flaw to cause a denial of service to applications that use the affected filesystems.

    Published:Jan 24, 2022
    Last Modified:Nov 21, 2024
    EPS:Aug 23, 2022
    EPSS Score:0.00242
    CVSS Score:5.5

    Affected Products

    Vendor
    Fedoraproject
    Product
    Fedora
    Vendor
    Kernel
    Product
    Util-linux

    Exploits

    https://www.openwall.com/lists/oss-security/2022/01/24/2https://www.openwall.com/lists/oss-security/2022/01/24/2

    Common Attack Pattern Enumeration and Classification (CAPEC)

    CAPEC-150 Collect Data from Common Resource Locations
    CAPEC-639 Probe System Files

    Related CVEs

    CVE-2026-54231 (CVSS 5.5) — A content injection vulnerability was found in the ABRT post-create event handler scripts in libreport. The ev…
    CVE-2026-54230 (CVSS 7) — A symlink following vulnerability was found in the ABRT post-create event handler scripts in libreport. Event …
    CVE-2026-35094 (CVSS 3.3) — A flaw was found in libinput. An attacker capable of deploying a Lua plugin file in specific system directorie…
    CVE-2026-35093 (CVSS 8.8) — A flaw was found in libinput. A local attacker who can place a specially crafted Lua bytecode file in certain …
    CVE-2024-3056 (CVSS 7.7) — A flaw was found in Podman. This issue may allow an attacker to create a specially crafted container that, whe…
    CVE-2024-6293 (CVSS 8.8) — Use after free in Dawn in Google Chrome prior to 126.0.6478.126 allowed a remote attacker to potentially explo…
    CVE-2024-6292 (CVSS 8.8) — Use after free in Dawn in Google Chrome prior to 126.0.6478.126 allowed a remote attacker to potentially explo…
    CVE-2024-6291 (CVSS 8.8) — Use after free in Swiftshader in Google Chrome prior to 126.0.6478.126 allowed a remote attacker to potentiall…
    CVE-2024-6290 (CVSS 8.8) — Use after free in Dawn in Google Chrome prior to 126.0.6478.126 allowed a remote attacker to potentially explo…
    CVE-2024-38277 (CVSS 5.4) — A unique key should be generated for a user's QR login key and their auto-login key, so the same key cannot be…

    References

    http://packetstormsecurity.com/files/170176/snap-confine-must_mkdir_and_open_with_perms-Race-Condition.html
    http://seclists.org/fulldisclosure/2022/Dec/4
    http://www.openwall.com/lists/oss-security/2022/11/30/2
    https://bugzilla.redhat.com/show_bug.cgi?id=2024631https://access.redhat.com/security/cve/CVE-2021-3995
    https://github.com/util-linux/util-linux/commit/57202f5713afa2af20ffbb6ab5331481d0396f8d
    https://mirrors.edge.kernel.org/pub/linux/utils/util-linux/v2.37/v2.37.3-ReleaseNotes
    https://security.gentoo.org/glsa/202401-08
    https://security.netapp.com/advisory/ntap-20221209-0002/
    https://www.openwall.com/lists/oss-security/2022/01/24/2
    http://packetstormsecurity.com/files/170176/snap-confine-must_mkdir_and_open_with_perms-Race-Condition.html
    http://seclists.org/fulldisclosure/2022/Dec/4
    http://www.openwall.com/lists/oss-security/2022/11/30/2
    https://bugzilla.redhat.com/show_bug.cgi?id=2024631https://access.redhat.com/security/cve/CVE-2021-3995
    https://github.com/util-linux/util-linux/commit/57202f5713afa2af20ffbb6ab5331481d0396f8d
    https://mirrors.edge.kernel.org/pub/linux/utils/util-linux/v2.37/v2.37.3-ReleaseNotes
    https://security.gentoo.org/glsa/202401-08
    https://security.netapp.com/advisory/ntap-20221209-0002/
    https://www.openwall.com/lists/oss-security/2022/01/24/2

    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