CVE-2026-74663
In the Linux kernel, the following vulnerability has been resolved:
net/sched: reject overly deep qdisc hierarchies
Deep qdisc hierarchies can lead to excessive recursion in qdisc tree walkers and exhaust the kernel stack. The existing loop check does not cover the create-and-graft path, so a hierarchy can still be extended by creating a new child qdisc below an already deep parent.
Store the hierarchy depth in struct Qdisc and update it when qdiscs are grafted. Reject new child qdiscs once the parent is already at the maximum allowed depth.
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: 0.13%
- 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 escalation85 % - Impacto principal
T1499.004Application or System Exploitationimpact75 % - Impacto secundario
T1529System Shutdown/Rebootimpact70 %
AV:L + PR:L sin UI:N = escalada local (T1068). Crear jerarquías qdisc profundas agota stack kernel causando DoS (T1499.004) o crash del sistema (T1529).
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/08dc49df1527b09d9ea225a7265bbf6c237097bf
- https://git.kernel.org/stable/c/2759acf08a3454866660edcd3ef4e64139f254a6
- https://git.kernel.org/stable/c/8ca8cdb74939581339e1ae370193c0adb5a85336
- https://git.kernel.org/stable/c/9f69bb9fdaa2fe64b68bb62fb84d405784bee540
- https://git.kernel.org/stable/c/a4b14a4df29d36458a943f9b521ddd0f940363cc
- https://git.kernel.org/stable/c/a627d36c2a94e18c8c105ae68008786dfd85592e
- https://git.kernel.org/stable/c/dedd34b0f2310e28c5f6d4875cfbf4b7ed821c01
- https://git.kernel.org/stable/c/e2d658c6427844cee5bc654b436ca68d680b6148
JSON original (NVD)
Mostrar
{
"id": "CVE-2026-74663",
"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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{
"status": "unaffected",
"version": "6.1.183",
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},
{
"status": "unaffected",
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{
"status": "unaffected",
"version": "6.12.104",
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},
{
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"version": "6.18.45",
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{
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{
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"versionType": "original_commit_for_fix",
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}
],
"programFiles": [
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],
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}
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}
],
"published": "2026-08-22T16:16:40.103",
"references": [
{
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{
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"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
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{
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"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
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{
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"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
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{
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"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
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"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/dedd34b0f2310e28c5f6d4875cfbf4b7ed821c01",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/e2d658c6427844cee5bc654b436ca68d680b6148",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
],
"vulnStatus": "Received",
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: reject overly deep qdisc hierarchies\n\nDeep qdisc hierarchies can lead to excessive recursion in qdisc tree\nwalkers and exhaust the kernel stack. The existing loop check does not\ncover the create-and-graft path, so a hierarchy can still be extended by\ncreating a new child qdisc below an already deep parent.\n\nStore the hierarchy depth in struct Qdisc and update it when qdiscs are\ngrafted. Reject new child qdiscs once the parent is already at the maximum\nallowed depth."
}
],
"lastModified": "2026-08-27T13:18:36.473",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}