CVE-2026-78408 (GCVE-0-2026-78408)
Vulnerability from cvelistv5
Published
2026-09-02 15:05
Modified
2026-10-21 17:51
Severity ?
7.9 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:C/C:N/I:H/A:H
CWE
  • CWE-775 - Missing Release of File Descriptor or Handle after Effective Lifetime
Summary
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.
References
Impacted products
Vendor Product Version
Red Hat Red Hat Hardened Images Unaffected: 2.42.2-3.4.hum1   < *
    cpe:/a:redhat:hummingbird:1
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