VULNERABILITY INTELLIGENCE
CVE-2026-78408
CVSS score7.9 HIGH
EPSS probability0.19%
CISA KEVNot currently listed
Published2026-09-02
Last modified2026-10-30
CVSS vectorCVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:C/C:N/I:H/A:H
Description
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.
Weakness classification
- secalert@redhat.com: CWE-775