{"schemaVersion":3,"id":"CVE-2026-78408","aliases":["ALPINE-CVE-2026-78408","UBUNTU-CVE-2026-78408","DEBIAN-CVE-2026-78408"],"status":"published","duplicateOf":null,"title":null,"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. 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