util-linux: util-linux: failed external mount helper still runs privileged X-mount post-hooks

When an external mount. helper runs but exits with a nonzero status, libmount still treats the helper invocation as successful and runs privileged post-mount hooks. A local unprivileged user with an /etc/fstab entry that uses the user option together with X-mount.idmap or X-mount.owner/group/mode...

CVE-2026-76642

util-linux (libmount component) versions through 2.41.5 and 2.42.2 fail to check the exit status of an external mount helper before executing privileged post-mount hooks. A local unprivileged user with an /etc/fstab entry using the user option combined with X-mount.idmap or X-mount.owner/group/mo...

CVE-2026-76642 util-linux libmount Privilege Escalation via Failed Mount Helper

util-linux versions through 2.41.5 and 2.42.2 fail to check mount helper exit status before running post-mount hooks, allowing unprivileged users to execute privileged operations on pre-existing filesystems. Attackers can exploit X-mount.idmap or X-mount.owner hooks to clone filesystems with...

CVE-2026-76642 util-linux libmount Privilege Escalation via Failed Mount Helper

util-linux versions through 2.41.5 and 2.42.2 fail to check mount helper exit status before running post-mount hooks, allowing unprivileged users to execute privileged operations on pre-existing filesystems. Attackers can exploit X-mount.idmap or X-mount.owner hooks to clone filesystems with...

CVE-2026-76642

When an external mount. helper runs but exits with a nonzero status, libmount still treats the helper invocation as successful and runs privileged post-mount hooks. A local unprivileged user with an /etc/fstab entry that uses the user option together with X-mount.idmap or X-mount.owner/group/mode...

Fedora 43 : util-linux (2026-a7ff7017ee)

The remote Fedora 43 host has a package installed that is affected by multiple vulnerabilities as referenced in the FEDORA-2026-a7ff7017ee advisory. upstream upgrade with security fixes: - CVE-2026-53612 - libmount: TOCTOU attack via ancestor directory swap during mount - CVE-2026-53613 - libmoun...

Fedora 44 : util-linux (2026-c70cb96ff1)

The remote Fedora 44 host has a package installed that is affected by multiple vulnerabilities as referenced in the FEDORA-2026-c70cb96ff1 advisory. upstream upgrade with security fixes: - CVE-2026-53612 - libmount: TOCTOU attack via ancestor directory swap during mount - CVE-2026-53613 - libmoun...

CVE-2026-53614

Local Privilege Escalation via LIBMOUNTFORCEMOUNT2 Environment Variable - nosuid/noexec Bypass in SUID mount8...

UBUNTU-CVE-2026-53614

Local Privilege Escalation via LIBMOUNTFORCEMOUNT2 Environment Variable - nosuid/noexec Bypass in SUID mount8...

PT-2026-53079

Name of the Vulnerable Software and Affected Versions openSUSE Tumbleweed versions prior to 2.42.2-1.1 Description A local privilege escalation exists in the SUID mount8 utility. An attacker can bypass nosuid and noexec restrictions by manipulating the LIBMOUNT FORCE MOUNT2 environment variable...

JLSEC-2025-193 A logic error was found in the libmount library of util-linux in the function that allows an...

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 a local user on a vulnerable system to unmount other users' filesystems that are either world-writable themselves like /tmp or mounted in a...

JLSEC-2025-192 A logic error was found in the libmount library of util-linux in the function that allows an...

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...

Unity Linux 20.1070e Security Update: util-linux (UTSA-2025-680643)

The Unity Linux 20 host has a package installed that is affected by a vulnerability as referenced in the UTSA-2025-680643 advisory. 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 a local...

Unity Linux 20.1070e Security Update: util-linux (UTSA-2025-680644)

The Unity Linux 20 host has a package installed that is affected by a vulnerability as referenced in the UTSA-2025-680644 advisory. 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...

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 a local user on a vulnerable system to unmount other users' filesystems that are either world-writable themselves (like /tmp) or mounted in a world-writable directory. An attacker may use this flaw to cause a denial of service to applications that use the affected filesystems.

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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.

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Huawei EulerOS: Security Advisory for util-linux (EulerOS-SA-2024-1951)

The remote host is missing an update for the Huawei EulerOS SPDX-FileCopyrightText: 2024 Greenbone AG Some text descriptions might be excerpted from a referenced sources, and are Copyright C by the respective right holders. SPDX-License-Identifier: GPL-2.0-only ifdescription...

Huawei EulerOS: Security Advisory for util-linux (EulerOS-SA-2024-1668)

The remote host is missing an update for the Huawei EulerOS SPDX-FileCopyrightText: 2024 Greenbone AG Some text descriptions might be excerpted from a referenced sources, and are Copyright C by the respective right holders. SPDX-License-Identifier: GPL-2.0-only ifdescription...

SUSE: Security Advisory (SUSE-SU-2024:1170-1)

The remote host is missing an update for the SPDX-FileCopyrightText: 2024 Greenbone AG Some text descriptions might be excerpted from a referenced sources, and are Copyright C by the respective right holders. SPDX-License-Identifier: GPL-2.0-only ifdescription...

openSUSE: Security Advisory for util (SUSE-SU-2024:1169-1)

The remote host is missing an update for the SPDX-FileCopyrightText: 2024 Greenbone AG Some text descriptions might be excerpted from a referenced sources, and are Copyright C by the respective right holders. SPDX-License-Identifier: GPL-2.0-only ifdescription...