Linux Distros Unpatched Vulnerability : CVE-2026-78408

critical Nessus Plugin ID 342439

Synopsis

The Linux/Unix host has one or more packages installed with a vulnerability that the vendor indicates will not be patched.

Description

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

- 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 attacker- controlled target can inherit root's ability to move host processes between cgroups. After a privileged operator uses --join-cgroup against that target, an unprivileged user can migrate and terminate unrelated root processes. (CVE-2026-78408)

Note that Nessus relies on the presence of the package as reported by the vendor.

Solution

There is no known solution at this time.

See Also

https://access.redhat.com/security/cve/cve-2026-78408

Plugin Details

Severity: Critical

ID: 342439

File Name: unpatched_CVE_2026_78408.nasl

Version: 1.1

Type: Local

Agent: unix

Family: Misc.

Published: 9/2/2026

Updated: 9/2/2026

Supported Sensors: Nessus Agent, Nessus

Risk Information

CVSS v2

Risk Factor: High

Base Score: 7.2

Temporal Score: 6.1

Vector: CVSS2#AV:L/AC:L/Au:N/C:C/I:C/A:C

CVSS Score Source: CVE-2026-78408

CVSS v3

Risk Factor: Critical

Base Score: 9.1

Temporal Score: 8.3

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H

Temporal Vector: CVSS:3.0/E:U/RL:U/RC:C

Vulnerability Information

CPE: cpe:/o:redhat:enterprise_linux:10, p-cpe:/a:redhat:enterprise_linux:libblkid-devel, p-cpe:/a:redhat:enterprise_linux:libblkid, p-cpe:/a:redhat:enterprise_linux:libfdisk-devel, p-cpe:/a:redhat:enterprise_linux:libfdisk, p-cpe:/a:redhat:enterprise_linux:libmount-devel, p-cpe:/a:redhat:enterprise_linux:libmount, p-cpe:/a:redhat:enterprise_linux:libsmartcols-devel, p-cpe:/a:redhat:enterprise_linux:libsmartcols, p-cpe:/a:redhat:enterprise_linux:libuuid-devel, p-cpe:/a:redhat:enterprise_linux:libuuid, p-cpe:/a:redhat:enterprise_linux:python3-libmount, p-cpe:/a:redhat:enterprise_linux:util-linux-core, p-cpe:/a:redhat:enterprise_linux:util-linux, p-cpe:/a:redhat:enterprise_linux:uuidd

Required KB Items: Host/local_checks_enabled, Host/cpu, global_settings/vendor_unpatched, Host/OS/identifier

Exploit Ease: No known exploits are available

Vulnerability Publication Date: 9/2/2026

Reference Information

CVE: CVE-2026-78408