CVE-2026-80718
In the Linux kernel, the following vulnerability has been resolved:
mm/percpu-km: fix bitmap overflow and accounting in pcpu_create_chunk()
In pcpu_create_chunk(), nr_pages is the total contiguous backing allocation, i.e., nr_units * pcpu_unit_pages, but pcpu_chunk_populated() uses it to set chunk->populated, whose size is pcpu_unit_pages, bitmap. Since bit N in chunk->populated means page offset N inside every unit is backed. When nr_units > 1, the function writes beyond chunk->populated. Fix it by using chunk->nr_pages.
It also fixes the global pcpu_nr_empty_pop_pages accounting, since pcpu_balance_free() only iterates up to chunk->nr_pages.
Leer descripción completaMostrar menos
Commit a63d4ac4ab609 ("percpu: make percpu-km set chunk->populated bitmap properly") introduced the bitmap overflow issue. Later, commit b539b87fed37f ("percpu: implmeent pcpu_nr_empty_pop_pages and chunk->nr_populated") added pcpu_nr_empty_pop_pages and caused the accounting issue.
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: 0.18%
- Percentil entre todas las CVEs puntuadas: 6
- 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 Interpreterexecution70 % - Impacto secundario
T1499.004Application or System Exploitationimpact60 %
Vulnerabilidad local en kernel (AV:L, PR:L) sin interacción del usuario que permite escalada de privilegios mediante overflow de bitmap en memoria del kernel percpu, con acceso confidencial, integridad y disponibilidad (C:H, I:H, A:H).
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/01504da375f5b19df195cb1cb1cf1dd184318f97
- https://git.kernel.org/stable/c/32134cf9211b83bed9076d0739c5906fbea4c763
- https://git.kernel.org/stable/c/5c7fc39bf19abb38a996aaad77b3e3a8f48581c3
- https://git.kernel.org/stable/c/5f43d2c1bea280dcdfabaf156c25e7402fb8039f
- https://git.kernel.org/stable/c/6fc7da2a052f2825fff785e860e67183f5acaaba
- https://git.kernel.org/stable/c/89b1b79c308818a715e75f28744b70d8940a07c9
- https://git.kernel.org/stable/c/92c43ac3c2b09eb16162e8144e73c00b7c3e29d6
- https://git.kernel.org/stable/c/a6940b84c8c035da465b7165fdfcfb005545724e
JSON original (NVD)
Mostrar
{
"id": "CVE-2026-80718",
"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
}
]
},
"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": "a63d4ac4ab6094c051a5a240260d16117a7a2f86",
"lessThan": "5f43d2c1bea280dcdfabaf156c25e7402fb8039f",
"versionType": "git"
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{
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{
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{
"status": "affected",
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"versionType": "git"
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{
"status": "affected",
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{
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],
"programFiles": [
"mm/percpu-km.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "3.18"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "3.18",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "5.10.265",
"versionType": "semver",
"lessThanOrEqual": "5.10.*"
},
{
"status": "unaffected",
"version": "5.15.216",
"versionType": "semver",
"lessThanOrEqual": "5.15.*"
},
{
"status": "unaffected",
"version": "6.1.183",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.151",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.103",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.44",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.1.8",
"versionType": "semver",
"lessThanOrEqual": "7.1.*"
},
{
"status": "unaffected",
"version": "7.2",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"mm/percpu-km.c"
],
"defaultStatus": "affected"
}
]
}
],
"published": "2026-08-28T08:16:57.563",
"references": [
{
"url": "https://git.kernel.org/stable/c/01504da375f5b19df195cb1cb1cf1dd184318f97",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
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"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/5c7fc39bf19abb38a996aaad77b3e3a8f48581c3",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/5f43d2c1bea280dcdfabaf156c25e7402fb8039f",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/6fc7da2a052f2825fff785e860e67183f5acaaba",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/89b1b79c308818a715e75f28744b70d8940a07c9",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/92c43ac3c2b09eb16162e8144e73c00b7c3e29d6",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/a6940b84c8c035da465b7165fdfcfb005545724e",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
],
"vulnStatus": "Received",
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm/percpu-km: fix bitmap overflow and accounting in pcpu_create_chunk()\n\nIn pcpu_create_chunk(), nr_pages is the total contiguous backing\nallocation, i.e., nr_units * pcpu_unit_pages, but pcpu_chunk_populated()\nuses it to set chunk->populated, whose size is pcpu_unit_pages, bitmap. \nSince bit N in chunk->populated means page offset N inside every unit is\nbacked. When nr_units > 1, the function writes beyond chunk->populated. \nFix it by using chunk->nr_pages.\n\nIt also fixes the global pcpu_nr_empty_pop_pages accounting, since\npcpu_balance_free() only iterates up to chunk->nr_pages.\n\nCommit a63d4ac4ab609 (\"percpu: make percpu-km set chunk->populated bitmap\nproperly\") introduced the bitmap overflow issue. Later, commit\nb539b87fed37f (\"percpu: implmeent pcpu_nr_empty_pop_pages and\nchunk->nr_populated\") added pcpu_nr_empty_pop_pages and caused the\naccounting issue."
}
],
"lastModified": "2026-08-29T07:16:53.323",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}