CVE-2026-78408
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.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:C/C:N/I:H/A:H
- Puntuación base: 7.9
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.19%
- Percentil entre todas las CVEs puntuadas: 8
- Fecha de la puntuación: 6/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
🎯 Técnicas ATT&CK
Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.
- Explotación
T1203Exploitation for Client Executionexecution75 % - Impacto principal
T1068Exploitation for Privilege Escalationprivilege escalation80 % - Impacto secundario
T1059Command and Scripting Interpreterexecution70 %
Requiere interacción de usuario (UI:R): operador privilegiado usa --join-cgroup. Acceso local (AV:L) + interacción = T1203. Impacto principal: escalada de privilegios (obtiene capacidades root). Secundario: ejecución de comandos (migrar/terminar procesos).
Inferido por nuestro agente de análisis a partir de la descripción oficial, el vector CVSS y la CWE, y comprobado por un supervisor. Puede contener errores.
🛡️ Mitigaciones ATT&CK que cubren estas técnicas
Tecnologías afectadas (1)
⚠ Inferidas por IA a partir de la descripción — NVD aún no ha analizado esta CVE; no son CPE verificados.
CWE
- CWE-775
Referencias
- https://access.redhat.com/errata/RHSA-2026:63162
- https://access.redhat.com/security/cve/CVE-2026-78408
- https://bugzilla.redhat.com/show_bug.cgi?id=2522497
- https://github.com/util-linux/util-linux/security/advisories/GHSA-55fx-f4gg-cfhj
- http://www.openwall.com/lists/oss-security/2026/09/05/2
- https://github.com/util-linux/util-linux/security/advisories/GHSA-55fx-f4gg-cfhj
JSON original (NVD)
Mostrar
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