CVE-2026-72491
In the Linux kernel, the following vulnerability has been resolved:
net/9p: fix race condition on rdma->state in trans_rdma.c
The rdma->state field is modified without holding req_lock in both recv_done() and p9_cm_event_handler(), while rdma_request() accesses the same field under the req_lock spinlock. This inconsistent locking creates a race condition:
The race can cause lost state transitions: recv_done() or the CM event handler could set state to FLUSHING/CLOSED while rdma_request() is concurrently checking or modifying state under the lock, leading to the FLUSHING transition being silently overwritten by CLOSING. This corrupts the connection state machine and can cause use-after-free on RDMA request objects during teardown.
Leer descripción completaMostrar menos
Fix by adding req_lock protection to all rdma->state modifications in recv_done() and p9_cm_event_handler(), matching the pattern already used in rdma_request(). Use spin_lock_irqsave/spin_unlock_irqrestore in the CM event handler since it can race with recv_done() which runs in softirq context.
Tested with a kernel module that races two threads (simulating rdma_request and recv_done/CM handler) on rdma->state with proper locking: 5.5M+ FLUSHING writes over 27M iterations with 0 lost transitions.
Detalles técnicos trazas, registros y código del informe original
- recv_done() running in softirq completion context sets rdma->state = P9_RDMA_FLUSHING without acquiring req_lock - p9_cm_event_handler() modifies rdma->state at multiple points (ADDR_RESOLVED, ROUTE_RESOLVED, ESTABLISHED, CLOSED) without req_lock - rdma_request() uses spin_lock_irqsave(&rdma->req_lock, flags) to protect the read-modify-write of rdma->state
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Puntuación base: 9.8
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.73%
- Percentil entre todas las CVEs puntuadas: 53
- 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 secundario
T1499.004Application or System Exploitationimpact60 %
Vulnerabilidad de condición de carrera en kernel Linux accesible remotamente (AV:N) sin autenticación. Corrupción de estado RDMA puede escalar privilegios o causar DoS por use-after-free.
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
- https://git.kernel.org/stable/c/13bf9879b778b2f4b260b45bed18f31806120d1e
- https://git.kernel.org/stable/c/151f8cf5b23d8a534d884432a82a6d54d5a61989
- https://git.kernel.org/stable/c/3970a19a80de530b801b6256354d4a529a9a2d6c
- https://git.kernel.org/stable/c/4cee2b8766045059d5e0b8114837b4a8efe827ac
- https://git.kernel.org/stable/c/5424138848eb7d7d8a7196676e90a2cbf2142454
- https://git.kernel.org/stable/c/7d54894a1ee265a72d70f7cae1da6cc774cccc71
- https://git.kernel.org/stable/c/8aadc136d8e8d8fc95d7982d213cfe2234dfcf2b
- https://git.kernel.org/stable/c/ebbcbe5c0db215feecc17def06178da443f4eea6
JSON original (NVD)
Mostrar
{
"id": "CVE-2026-72491",
"cveTags": [],
"metrics": {
"cvssMetricV31": [
{
"type": "Secondary",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 9.8,
"attackVector": "NETWORK",
"baseSeverity": "CRITICAL",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
"integrityImpact": "HIGH",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"availabilityImpact": "HIGH",
"privilegesRequired": "NONE",
"confidentialityImpact": "HIGH"
},
"impactScore": 5.9,
"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": "473c7dd1d7b59ff8f88a5154737e3eac78a96e5b",
"lessThan": "4cee2b8766045059d5e0b8114837b4a8efe827ac",
"versionType": "git"
},
{
"status": "affected",
"version": "473c7dd1d7b59ff8f88a5154737e3eac78a96e5b",
"lessThan": "5424138848eb7d7d8a7196676e90a2cbf2142454",
"versionType": "git"
},
{
"status": "affected",
"version": "473c7dd1d7b59ff8f88a5154737e3eac78a96e5b",
"lessThan": "3970a19a80de530b801b6256354d4a529a9a2d6c",
"versionType": "git"
},
{
"status": "affected",
"version": "473c7dd1d7b59ff8f88a5154737e3eac78a96e5b",
"lessThan": "8aadc136d8e8d8fc95d7982d213cfe2234dfcf2b",
"versionType": "git"
},
{
"status": "affected",
"version": "473c7dd1d7b59ff8f88a5154737e3eac78a96e5b",
"lessThan": "151f8cf5b23d8a534d884432a82a6d54d5a61989",
"versionType": "git"
},
{
"status": "affected",
"version": "473c7dd1d7b59ff8f88a5154737e3eac78a96e5b",
"lessThan": "13bf9879b778b2f4b260b45bed18f31806120d1e",
"versionType": "git"
},
{
"status": "affected",
"version": "473c7dd1d7b59ff8f88a5154737e3eac78a96e5b",
"lessThan": "ebbcbe5c0db215feecc17def06178da443f4eea6",
"versionType": "git"
},
{
"status": "affected",
"version": "473c7dd1d7b59ff8f88a5154737e3eac78a96e5b",
"lessThan": "7d54894a1ee265a72d70f7cae1da6cc774cccc71",
"versionType": "git"
},
{
"status": "affected",
"version": "3479b3c35e82ed10aa0ca2ee9e78c4eded06ba62",
"versionType": "git"
},
{
"status": "affected",
"version": "c01ddaa54d7411e964ffd250c018d8469c5852f2",
"versionType": "git"
},
{
"status": "affected",
"version": "9e69c673fe077b8dc491cd8406c9bdcb1f76dee2",
"versionType": "git"
},
{
"status": "affected",
"version": "e48e7e27e4dfd00c81e0381e7cee610cce021452",
"versionType": "git"
},
{
"status": "affected",
"version": "4.4.185",
"lessThan": "4.5",
"versionType": "semver"
},
{
"status": "affected",
"version": "4.9.185",
"lessThan": "4.10",
"versionType": "semver"
},
{
"status": "affected",
"version": "4.14.132",
"lessThan": "4.15",
"versionType": "semver"
},
{
"status": "affected",
"version": "4.19.57",
"lessThan": "4.20",
"versionType": "semver"
}
],
"programFiles": [
"net/9p/trans_rdma.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "4.20"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "4.20",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "5.10.261",
"versionType": "semver",
"lessThanOrEqual": "5.10.*"
},
{
"status": "unaffected",
"version": "5.15.212",
"versionType": "semver",
"lessThanOrEqual": "5.15.*"
},
{
"status": "unaffected",
"version": "6.1.178",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.145",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.97",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.40",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.1.5",
"versionType": "semver",
"lessThanOrEqual": "7.1.*"
},
{
"status": "unaffected",
"version": "7.2",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"net/9p/trans_rdma.c"
],
"defaultStatus": "affected"
}
]
}
],
"published": "2026-08-15T06:22:23.400",
"references": [
{
"url": "https://git.kernel.org/stable/c/13bf9879b778b2f4b260b45bed18f31806120d1e",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/151f8cf5b23d8a534d884432a82a6d54d5a61989",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/3970a19a80de530b801b6256354d4a529a9a2d6c",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/4cee2b8766045059d5e0b8114837b4a8efe827ac",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/5424138848eb7d7d8a7196676e90a2cbf2142454",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/7d54894a1ee265a72d70f7cae1da6cc774cccc71",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/8aadc136d8e8d8fc95d7982d213cfe2234dfcf2b",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/ebbcbe5c0db215feecc17def06178da443f4eea6",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
],
"vulnStatus": "Received",
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/9p: fix race condition on rdma->state in trans_rdma.c\n\nThe rdma->state field is modified without holding req_lock in both\nrecv_done() and p9_cm_event_handler(), while rdma_request() accesses\nthe same field under the req_lock spinlock. This inconsistent locking\ncreates a race condition:\n\n- recv_done() running in softirq completion context sets\n rdma->state = P9_RDMA_FLUSHING without acquiring req_lock\n\n- p9_cm_event_handler() modifies rdma->state at multiple points\n (ADDR_RESOLVED, ROUTE_RESOLVED, ESTABLISHED, CLOSED) without\n req_lock\n\n- rdma_request() uses spin_lock_irqsave(&rdma->req_lock, flags) to\n protect the read-modify-write of rdma->state\n\nThe race can cause lost state transitions: recv_done() or the CM\nevent handler could set state to FLUSHING/CLOSED while rdma_request()\nis concurrently checking or modifying state under the lock, leading to\nthe FLUSHING transition being silently overwritten by CLOSING. This\ncorrupts the connection state machine and can cause use-after-free on\nRDMA request objects during teardown.\n\nFix by adding req_lock protection to all rdma->state modifications in\nrecv_done() and p9_cm_event_handler(), matching the pattern already\nused in rdma_request(). Use spin_lock_irqsave/spin_unlock_irqrestore\nin the CM event handler since it can race with recv_done() which runs\nin softirq context.\n\nTested with a kernel module that races two threads (simulating\nrdma_request and recv_done/CM handler) on rdma->state with proper\nlocking: 5.5M+ FLUSHING writes over 27M iterations with 0 lost\ntransitions."
}
],
"lastModified": "2026-08-17T06:19:17.397",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}