CVE-2026-64563
In the Linux kernel, the following vulnerability has been resolved:
rhashtable: clear stale iter->p on table restart
rhashtable_walk_start_check() has two restart paths when resuming a walk. When iter->walker.tbl is valid, it re-validates iter->p against the table and sets iter->p = NULL if the object is gone. When iter->walker.tbl is NULL (table was freed during resize), it resets slot and skip but forgets to clear iter->p.
rhashtable_walk_next() then dereferences the stale iter->p, reading freed memory. This is a use-after-free.
Any caller that does multi-fragment rhashtable walks across walk_stop/walk_start boundaries is affected. Concrete cases include netlink_diag (__netlink_diag_dump in net/netlink/diag.c) and TIPC (tipc_nl_sk_walk in net/tipc/socket.c).
Detalles técnicos trazas, registros y código del informe original
Crash stack (netlink_diag): BUG: KASAN: slab-use-after-free in rhashtable_walk_next+0x365/0x3c0 Read of size 8 at addr ffff88801a9d2438 (freed kmalloc-2k, offset 1080) Call Trace: rhashtable_walk_next+0x365/0x3c0 (lib/rhashtable.c:1016) __netlink_diag_dump+0x160/0x760 (net/netlink/diag.c:122) netlink_diag_dump+0xc2/0x240 netlink_dump+0x5bc/0x1270 netlink_recvmsg+0x7a3/0x980 sock_recvmsg+0x1bc/0x200 __sys_recvfrom+0x1d4/0x2c0
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: 0.12%
- Percentil entre todas las CVEs puntuadas: 2
- 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
T1068Exploitation for Privilege Escalationprivilege escalation90 % - Impacto principal
T1005Data from Local Systemcollection85 % - Impacto secundario
T1499.004Application or System Exploitationimpact75 %
Vulnerabilidad de use-after-free (CWE-416) en kernel local requiere PR:L; lectura de memoria liberada (KASAN) y crash potencial por DoS.
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/042fda5c088015f18838e5c692659a7be60aeb26
- https://git.kernel.org/stable/c/0955b65c2b47c30b439e2cf1b1e375073aa0413a
- https://git.kernel.org/stable/c/3ff7c1dbf722cf3fa538672452ba182318e0fcc3
- https://git.kernel.org/stable/c/4169d9fb92f313ff8e7e83d733c1ecdcc93eebd3
- https://git.kernel.org/stable/c/8173f7e2ce67e6ca1d4763f3da14e5b01ce77456
- https://git.kernel.org/stable/c/a0406c40c6638c5ae50257db6297b2fba6c9ba16
- https://git.kernel.org/stable/c/ba510b5e9fe396497d31162acb579f210adfe6c8
- https://git.kernel.org/stable/c/c39643ad99fea749be50615550e8f0e6d6e60694
JSON original (NVD)
Mostrar
{
"id": "CVE-2026-64563",
"cveTags": [],
"metrics": {
"cvssMetricV31": [
{
"type": "Secondary",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 7.8,
"attackVector": "LOCAL",
"baseSeverity": "HIGH",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"integrityImpact": "HIGH",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"availabilityImpact": "HIGH",
"privilegesRequired": "LOW",
"confidentialityImpact": "HIGH"
},
"impactScore": 5.9,
"exploitabilityScore": 1.8
}
]
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"affected": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"affectedData": [
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"vendor": "Linux",
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"status": "affected",
"version": "5d240a8936f6a1d3ece06701e8c4d830a2eca8a8",
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"programFiles": [
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],
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{
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"vendor": "Linux",
"product": "Linux",
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{
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{
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{
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},
{
"status": "unaffected",
"version": "6.6.151",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.103",
"versionType": "semver",
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},
{
"status": "unaffected",
"version": "6.18.42",
"versionType": "semver",
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{
"status": "unaffected",
"version": "7.1.6",
"versionType": "semver",
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{
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"version": "7.2",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
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],
"defaultStatus": "affected"
}
]
}
],
"published": "2026-08-04T07:16:31.220",
"references": [
{
"url": "https://git.kernel.org/stable/c/042fda5c088015f18838e5c692659a7be60aeb26",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
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"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/3ff7c1dbf722cf3fa538672452ba182318e0fcc3",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/4169d9fb92f313ff8e7e83d733c1ecdcc93eebd3",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
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"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
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{
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"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/ba510b5e9fe396497d31162acb579f210adfe6c8",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/c39643ad99fea749be50615550e8f0e6d6e60694",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
],
"vulnStatus": "Received",
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nrhashtable: clear stale iter->p on table restart\n\nrhashtable_walk_start_check() has two restart paths when resuming a walk.\nWhen iter->walker.tbl is valid, it re-validates iter->p against the table\nand sets iter->p = NULL if the object is gone. When iter->walker.tbl is\nNULL (table was freed during resize), it resets slot and skip but forgets\nto clear iter->p.\n\nrhashtable_walk_next() then dereferences the stale iter->p, reading\nfreed memory. This is a use-after-free.\n\nAny caller that does multi-fragment rhashtable walks across\nwalk_stop/walk_start boundaries is affected. Concrete cases include\nnetlink_diag (__netlink_diag_dump in net/netlink/diag.c) and TIPC\n(tipc_nl_sk_walk in net/tipc/socket.c).\n\nCrash stack (netlink_diag):\n BUG: KASAN: slab-use-after-free in rhashtable_walk_next+0x365/0x3c0\n Read of size 8 at addr ffff88801a9d2438 (freed kmalloc-2k, offset 1080)\n Call Trace:\n rhashtable_walk_next+0x365/0x3c0 (lib/rhashtable.c:1016)\n __netlink_diag_dump+0x160/0x760 (net/netlink/diag.c:122)\n netlink_diag_dump+0xc2/0x240\n netlink_dump+0x5bc/0x1270\n netlink_recvmsg+0x7a3/0x980\n sock_recvmsg+0x1bc/0x200\n __sys_recvfrom+0x1d4/0x2c0"
}
],
"lastModified": "2026-08-19T17:20:16.117",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}