CVE-2026-90149
Estado: RecibidaAlta (7.5)—
In the Linux kernel, the following vulnerability has been resolved:
NFSv4/flexfiles: fix NULL dereference for NFSv4.0 data servers
flexfiles accepts NFSv4.0 data servers, but two NFSv4 code paths assume the data server client has a session. Unlike NFSv4.1+, an NFSv4.0 client has no session (clp->cl_session is NULL; it uses clp->cl_slot_tbl), so I/O to a v4.0 flexfiles DS oopses:
Detalles técnicos trazas, registros y código del informe original
- nfs4_init_ds_session() dereferences clp->cl_session->session_state
while seeding the DS lease. It also only seeds cl_lease_time when
NFS4_SESSION_INITING is set; without a session that never happens, so
cl_lease_time stays 0 and nfs4_renew_state() busy-loops, requeuing
every 5 seconds. Seed the lease whenever there is no session and
return before touching session state.
- ff_layout_async_handle_error_v4() dereferences
clp->cl_session->fc_slot_table on every DS I/O error. Fall back to the
v4.0 transport slot table (clp->cl_slot_tbl) when there is no session.CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- Puntuación base: 7.5
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.61%
- Percentil entre todas las CVEs puntuadas: 47
- 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
T1190Exploit Public-Facing Applicationinitial access75 % - Impacto principal
T1499.004Application or System Exploitationimpact80 %
Vulnerabilidad de denegación de servicio en kernel Linux (NFSv4) explotable remotamente sin autenticación. NULL dereference causa oops/crash del sistema. Vector AV:N/AC:L/PR:N/UI:N con impacto A:H confirma DoS de aplicación.
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.
Referencias
JSON original (NVD)
Mostrar
{
"id": "CVE-2026-90149",
"cveTags": [],
"metrics": {
"cvssMetricV31": [
{
"type": "Secondary",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 7.5,
"attackVector": "NETWORK",
"baseSeverity": "HIGH",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
"integrityImpact": "NONE",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"availabilityImpact": "HIGH",
"privilegesRequired": "NONE",
"confidentialityImpact": "NONE"
},
"impactScore": 3.6,
"exploitabilityScore": 3.9
}
]
},
"affected": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"affectedData": [
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "a7878ca140084ec267ede48fce64d7e60f6d873e",
"lessThan": "163c16e01f53fc8eb8d0f3484ae6c382265ecbbd",
"versionType": "git"
},
{
"status": "affected",
"version": "a7878ca140084ec267ede48fce64d7e60f6d873e",
"lessThan": "436a214514e24103159aea455147d58b44a8a585",
"versionType": "git"
},
{
"status": "affected",
"version": "a7878ca140084ec267ede48fce64d7e60f6d873e",
"lessThan": "2b03ebbf8d5e8f6af4ecd6c65375232dd1ec32cc",
"versionType": "git"
}
],
"programFiles": [
"fs/nfs/flexfilelayout/flexfilelayout.c",
"fs/nfs/nfs4session.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "4.12"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "4.12",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.18.52",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.2.6",
"versionType": "semver",
"lessThanOrEqual": "7.2.*"
},
{
"status": "unaffected",
"version": "7.3-rc1",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"fs/nfs/flexfilelayout/flexfilelayout.c",
"fs/nfs/nfs4session.c"
],
"defaultStatus": "affected"
}
]
}
],
"published": "2026-09-17T17:17:07.830",
"references": [
{
"url": "https://git.kernel.org/stable/c/163c16e01f53fc8eb8d0f3484ae6c382265ecbbd",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/2b03ebbf8d5e8f6af4ecd6c65375232dd1ec32cc",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/436a214514e24103159aea455147d58b44a8a585",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
],
"vulnStatus": "Received",
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nNFSv4/flexfiles: fix NULL dereference for NFSv4.0 data servers\n\nflexfiles accepts NFSv4.0 data servers, but two NFSv4 code paths assume\nthe data server client has a session. Unlike NFSv4.1+, an NFSv4.0 client\nhas no session (clp->cl_session is NULL; it uses clp->cl_slot_tbl), so\nI/O to a v4.0 flexfiles DS oopses:\n\n - nfs4_init_ds_session() dereferences clp->cl_session->session_state\n while seeding the DS lease. It also only seeds cl_lease_time when\n NFS4_SESSION_INITING is set; without a session that never happens, so\n cl_lease_time stays 0 and nfs4_renew_state() busy-loops, requeuing\n every 5 seconds. Seed the lease whenever there is no session and\n return before touching session state.\n\n - ff_layout_async_handle_error_v4() dereferences\n clp->cl_session->fc_slot_table on every DS I/O error. Fall back to the\n v4.0 transport slot table (clp->cl_slot_tbl) when there is no session."
}
],
"lastModified": "2026-09-18T18:17:44.120",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}