util-linux: util-linux: nsenter --join-cgroup leaks root cgroup migration authority

The nsenter --join-cgroup option opens the target cgroup.procs file as root and leaves that file descriptor open across later namespace and credential changes and across execve. Because the kernel checks later cgroup migrations using the credentials from the original open, a program run in an...

util-linux: util-linux: restricted bind mounts do not pin the source, allowing X-mount.owner/group/mode redirection

A flaw was found in util-linux. Restricted bind mounts take the source path from fstab but do not pin that source before the privileged mount. A local unprivileged user who can replace the authorized source or a writable ancestor can redirect SUID mount8 to bind another host directory. If the fst...

util-linux: util-linux: X-mount.subdir detached-tree resolution can escape via intermediate symlinks

The X-mount.subdir option uses a detached-tree fast path on Linux 6.15 and later and passes the configured subdirectory to opentree with ATSYMLINKNOFOLLOW. That flag does not stop intermediate symlink traversal or keep resolution inside the newly mounted filesystem. A local unprivileged user with...

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...

Important: Red Hat Security Advisory: Red Hat Hardened Images RPMs Security Update

An update for Red Hat Hardened Images RPMs is now available. This update includes the following RPMs: util-linux: libblkid-2.42.2-3.4.hum1 aarch64, x8664 libblkid-devel-2.42.2-3.4.hum1 aarch64, x8664 libfdisk-2.42.2-3.4.hum1 aarch64, x8664 libfdisk-devel-2.42.2-3.4.hum1 aarch64, x8664...

CVE-2026-76642

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

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...

EUVD-2026-70382

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 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...

PT-2026-90896

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: Detection of Error Condition Without Action

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...

AZL-99393 CVE-2026-78408 affecting package util-linux for versions less than 2.40.2-6

The nsenter --join-cgroup option opens the target cgroup.procs file as root and leaves that file descriptor open across later namespace and credential changes and across execve. Because the kernel checks later cgroup migrations using the credentials from the original open, a program run in an...

AZL-99390 CVE-2026-78410 affecting package util-linux for versions less than 2.40.2-6

A flaw was found in util-linux. Restricted bind mounts take the source path from fstab but do not pin that source before the privileged mount. A local unprivileged user who can replace the authorized source or a writable ancestor can redirect SUID mount8 to bind another host directory. If the fst...

CVE-2026-78410

A flaw was found in util-linux. Restricted bind mounts take the source path from fstab but do not pin that source before the privileged mount. A local unprivileged user who can replace the authorized source or a writable ancestor can redirect SUID mount8 to bind another host directory. If the fst...

ALPINE-CVE-2026-78410

A flaw was found in util-linux. Restricted bind mounts take the source path from fstab but do not pin that source before the privileged mount. A local unprivileged user who can replace the authorized source or a writable ancestor can redirect SUID mount8 to bind another host directory. If the fst...

DEBIAN-CVE-2026-78410

A flaw was found in util-linux. Restricted bind mounts take the source path from fstab but do not pin that source before the privileged mount. A local unprivileged user who can replace the authorized source or a writable ancestor can redirect SUID mount8 to bind another host directory. If the fst...

CVE-2026-78410

A flaw was found in util-linux. Restricted bind mounts take the source path from fstab but do not pin that source before the privileged mount. A local unprivileged user who can replace the authorized source or a writable ancestor can redirect SUID mount8 to bind another host directory. If the fst...