CVE-2026-89782
In the Linux kernel, the following vulnerability has been resolved:
fs/ntfs3: reject restart table growth beyond U16_MAX entries
During $LogFile replay, log_replay() indexes the transaction table by the transact_id taken from the log record header. check_log_rec() only verifies that transact_id is non-zero and properly aligned, not its magnitude, so a crafted image can request an arbitrarily large index.
alloc_rsttbl_from_idx() grows the table to cover that index via extend_rsttbl(), which passes the new entry count to init_rsttbl():
used + add is computed as u32 but init_rsttbl() takes a u16, and the count is stored in struct RESTART_TABLE as a __le16.
Leer descripción completaMostrar menos
When used + add exceeds U16_MAX it is truncated, init_rsttbl() allocates a table far smaller than the index requires, and alloc_rsttbl_from_idx() then dereferences and writes at the original, untruncated offset -- an out-of-bounds access past the allocation, reachable by mounting a crafted NTFS image.
A restart table is limited to U16_MAX entries by its __le16 count, so a larger growth request is invalid input. Reject it in extend_rsttbl(); all callers already handle a NULL return.
Detalles técnicos trazas, registros y código del informe original
rt = init_rsttbl(esize, used + add); BUG: KASAN: use-after-free in alloc_rsttbl_from_idx (fs/ntfs3/fslog.c:950) Read of size 4 at addr ffff8880327ffff8 by task exploit alloc_rsttbl_from_idx (fs/ntfs3/fslog.c:950) log_replay (fs/ntfs3/fslog.c:4562) ntfs_loadlog_and_replay (fs/ntfs3/fsntfs.c:324) ntfs_fill_super (fs/ntfs3/super.c:1393) get_tree_bdev_flags vfs_get_tree path_mount __x64_sys_mount
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Puntuación base: 8.4
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 escalation95 % - Impacto principal
T1499.004Application or System Exploitationimpact85 % - Impacto secundario
T1565.001Stored Data Manipulationimpact75 %
Acceso local sin interacción (AV:L/PR:N/UI:N) explotable montando imagen NTFS crafted. Desbordamiento de buffer causa denegación de servicio (KASAN use-after-free) e impacto en integridad.
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/111f8d74a19d85942ecbb3aba78f6f3c88e59391
- https://git.kernel.org/stable/c/339e59996ff193adcf1c438cf05f19e753beb3a7
- https://git.kernel.org/stable/c/967a5ff8a614d10126b6d46db1ac040948d6cb42
- https://git.kernel.org/stable/c/aad605a450611e2a7b7cf9dd5724004d39192bfb
- https://git.kernel.org/stable/c/be218a01aadffe33ed4fc73e25276d676ebbd09d
- https://git.kernel.org/stable/c/caa0ec3fc44a13d7c21d78e4722f4f05f87ccf56
- https://git.kernel.org/stable/c/ecde45cd81dc28f5696c312c5ce5a509962e9ab1
JSON original (NVD)
Mostrar
{
"id": "CVE-2026-89782",
"cveTags": [],
"metrics": {
"cvssMetricV31": [
{
"type": "Secondary",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 8.4,
"attackVector": "LOCAL",
"baseSeverity": "HIGH",
"vectorString": "CVSS:3.1/AV:L/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": 2.5
}
]
},
"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": "b46acd6a6a627d876898e1c84d3f84902264b445",
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"versionType": "git"
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],
"programFiles": [
"fs/ntfs3/fslog.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "5.15"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "5.15",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "5.15.221",
"versionType": "semver",
"lessThanOrEqual": "5.15.*"
},
{
"status": "unaffected",
"version": "6.1.188",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.157",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.110",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"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/ntfs3/fslog.c"
],
"defaultStatus": "affected"
}
]
}
],
"published": "2026-09-16T09:17:08.800",
"references": [
{
"url": "https://git.kernel.org/stable/c/111f8d74a19d85942ecbb3aba78f6f3c88e59391",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/339e59996ff193adcf1c438cf05f19e753beb3a7",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/967a5ff8a614d10126b6d46db1ac040948d6cb42",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/aad605a450611e2a7b7cf9dd5724004d39192bfb",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/be218a01aadffe33ed4fc73e25276d676ebbd09d",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/caa0ec3fc44a13d7c21d78e4722f4f05f87ccf56",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/ecde45cd81dc28f5696c312c5ce5a509962e9ab1",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
],
"vulnStatus": "Received",
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nfs/ntfs3: reject restart table growth beyond U16_MAX entries\n\nDuring $LogFile replay, log_replay() indexes the transaction table by the\ntransact_id taken from the log record header. check_log_rec() only\nverifies that transact_id is non-zero and properly aligned, not its\nmagnitude, so a crafted image can request an arbitrarily large index.\n\nalloc_rsttbl_from_idx() grows the table to cover that index via\nextend_rsttbl(), which passes the new entry count to init_rsttbl():\n\n\trt = init_rsttbl(esize, used + add);\n\nused + add is computed as u32 but init_rsttbl() takes a u16, and the\ncount is stored in struct RESTART_TABLE as a __le16. When used + add\nexceeds U16_MAX it is truncated, init_rsttbl() allocates a table far\nsmaller than the index requires, and alloc_rsttbl_from_idx() then\ndereferences and writes at the original, untruncated offset -- an\nout-of-bounds access past the allocation, reachable by mounting a\ncrafted NTFS image.\n\n BUG: KASAN: use-after-free in alloc_rsttbl_from_idx (fs/ntfs3/fslog.c:950)\n Read of size 4 at addr ffff8880327ffff8 by task exploit\n alloc_rsttbl_from_idx (fs/ntfs3/fslog.c:950)\n log_replay (fs/ntfs3/fslog.c:4562)\n ntfs_loadlog_and_replay (fs/ntfs3/fsntfs.c:324)\n ntfs_fill_super (fs/ntfs3/super.c:1393)\n get_tree_bdev_flags\n vfs_get_tree\n path_mount\n __x64_sys_mount\n\nA restart table is limited to U16_MAX entries by its __le16 count, so a\nlarger growth request is invalid input. Reject it in extend_rsttbl();\nall callers already handle a NULL return."
}
],
"lastModified": "2026-09-16T15:18:08.577",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}