CVE-2026-64027
In the Linux kernel, the following vulnerability has been resolved:
net: shaper: rework the VALID marking (again)
Recent commit changed the semantics from NOT_VALID to VALID. I didn't realize that the flags are not stored atomically with the entry in XArray. There's still a race of reader observing a VALID mark for a slot, getting interrupted, writer replacing the entry with a different one, reader continuing, fetching the entry which is now a different pointer than the pointer for which VALID was meant.
The biggest consequence of this is that we may see a UAF since net_shaper_rollback() assumed that entries without VALID can be freed without observing RCU.
Leer descripción completaMostrar menos
Looks like the XArray marks are buying us nothing at this point. Let's convert the code to an explicit valid field. The smp_load_acquire() / smp_store_release() barriers are marginally cleaner.
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: 0.17%
- Percentil entre todas las CVEs puntuadas: 6
- 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 %
Vulnerabilidad local (AV:L/PR:L) en kernel Linux con race condition que causa UAF; impacto DoS por kernel panic o crash de servicios.
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
JSON original (NVD)
Mostrar
{
"id": "CVE-2026-64027",
"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": "93954b40f6a4fc43226c01a15b02732f884500f1",
"lessThan": "2417df5e7bb4184b9d3a2988036bf2c46e594545",
"versionType": "git"
},
{
"status": "affected",
"version": "93954b40f6a4fc43226c01a15b02732f884500f1",
"lessThan": "96ea960dd40fd55302e0fd755176f26a95e6a50c",
"versionType": "git"
},
{
"status": "affected",
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"lessThan": "b8d7519352ba8c6df83259295d4a3bad093cae90",
"versionType": "git"
}
],
"programFiles": [
"include/net/net_shaper.h",
"net/shaper/shaper.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "6.13"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "6.13",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.18.34",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.0.11",
"versionType": "semver",
"lessThanOrEqual": "7.0.*"
},
{
"status": "unaffected",
"version": "7.1",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"include/net/net_shaper.h",
"net/shaper/shaper.c"
],
"defaultStatus": "affected"
}
]
}
],
"published": "2026-07-19T16:17:42.777",
"references": [
{
"url": "https://git.kernel.org/stable/c/2417df5e7bb4184b9d3a2988036bf2c46e594545",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/96ea960dd40fd55302e0fd755176f26a95e6a50c",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/b8d7519352ba8c6df83259295d4a3bad093cae90",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
],
"vulnStatus": "Awaiting Analysis",
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: shaper: rework the VALID marking (again)\n\nRecent commit changed the semantics from NOT_VALID to VALID.\nI didn't realize that the flags are not stored atomically\nwith the entry in XArray. There's still a race of reader\nobserving a VALID mark for a slot, getting interrupted,\nwriter replacing the entry with a different one, reader\ncontinuing, fetching the entry which is now a different\npointer than the pointer for which VALID was meant.\n\nThe biggest consequence of this is that we may see a UAF\nsince net_shaper_rollback() assumed that entries without\nVALID can be freed without observing RCU.\n\nLooks like the XArray marks are buying us nothing at this\npoint. Let's convert the code to an explicit valid field.\nThe smp_load_acquire() / smp_store_release() barriers are\nmarginally cleaner."
}
],
"lastModified": "2026-07-30T14:59:47.950",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}