CVE-2026-33150
libfuse is the reference implementation of the Linux FUSE. From version 3.18.0 to before version 3.18.2, a use-after-free vulnerability in the io_uring subsystem of libfuse allows a local attacker to crash FUSE filesystem processes and potentially execute arbitrary code. When io_uring thread creation fails due to resource exhaustion (e.g., cgroup pids.max), fuse_uring_start() frees the ring pool structure but stores the dangling pointer in the session state, leading to a use-after-free when the session shuts down. The trigger is reliable in containerized environments where cgroup pids.max limits naturally constrain thread creation. This issue has been patched in version 3.18.2.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- Puntuación base: 7.8
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: 5/10/2026
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
T1068Exploitation for Privilege Escalationprivilege escalation85 % - Impacto principal
T1059Command and Scripting Interpreterexecution75 % - Impacto secundario
T1499.004Application or System Exploitationimpact80 %
AV:L sin UI requiere acceso local (T1068). El use-after-free permite ejecución arbitraria de código (T1059) y negación de servicio (T1499.004) contra procesos FUSE, explotable en entornos containerizados con límites de recursos.
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)
CWE
- CWE-416
- CWE-825
Referencias
- https://github.com/libfuse/libfuse/commit/49fcd891a58f622c098e2ca67d66086f7b213836
- https://github.com/libfuse/libfuse/releases/tag/fuse-3.18.2
- https://github.com/libfuse/libfuse/security/advisories/GHSA-qxv7-xrc2-qmfx
- https://access.redhat.com/security/cve/CVE-2026-33150
- https://bugzilla.redhat.com/show_bug.cgi?id=2449771
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-33150.json
JSON original (NVD)
Mostrar
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