CVE-2026-89774
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: SCO: hold sk properly in sco_conn_ready
sk deref in sco_conn_ready must be done either under conn->lock, or holding a refcount, to avoid concurrent close. conn->sk and parent sk is currently accessed without either, and without checking parent->sk_state:
and similarly for access to sco_get_sock_listen() return value.
Fix possible UAF by holding sk refcount in sco_conn_ready() and making sco_get_sock_listen() increase refcount. Also recheck after lock_sock that the socket is still valid. Adjust conn->sk locking so it's protected also by lock_sock() of the associated socket if any.
Detalles técnicos trazas, registros y código del informe original
[Task 1] [Task 2]
sco_sock_release
sco_conn_ready
sk = conn->sk
lock_sock(sk)
conn->sk = NULL
lock_sock(sk)
release_sock(sk)
sco_sock_kill(sk)
UAF on sk derefCVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Puntuación base: 8.8
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.40%
- Percentil entre todas las CVEs puntuadas: 32
- 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
T1210Exploitation of Remote Serviceslateral movement75 % - Impacto principal
T1068Exploitation for Privilege Escalationprivilege escalation65 %
UAF en kernel Bluetooth (AV:A, red adyacente) requiere acceso local o adyacente; explotación de servicio remoto. Impacto: denegación o ejecución con privilegios de kernel.
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/4e37f6452d586b95c346a9abdd2fb80b67794f39
- https://git.kernel.org/stable/c/50aae396dc30377bec8e3b181b8346f8fd38f7d8
- https://git.kernel.org/stable/c/6e3840578aaad1a296aab1eaaa89ea3b7d5cbae1
- https://git.kernel.org/stable/c/7199c78c3a3e399a4dc439d845826793880ccedc
- https://git.kernel.org/stable/c/73cb063f5ec6ca51eb1e246c6d332563002ac277
- https://git.kernel.org/stable/c/d141d9b769bcd1b747898528c5023270cda040f2
JSON original (NVD)
Mostrar
{
"id": "CVE-2026-89774",
"cveTags": [],
"metrics": {
"cvssMetricV31": [
{
"type": "Secondary",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 8.8,
"attackVector": "ADJACENT_NETWORK",
"baseSeverity": "HIGH",
"vectorString": "CVSS:3.1/AV:A/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": 2.8
}
]
},
"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": "27c24fda62b601d6f9ca5e992502578c4310876f",
"lessThan": "50aae396dc30377bec8e3b181b8346f8fd38f7d8",
"versionType": "git"
},
{
"status": "affected",
"version": "27c24fda62b601d6f9ca5e992502578c4310876f",
"lessThan": "6e3840578aaad1a296aab1eaaa89ea3b7d5cbae1",
"versionType": "git"
},
{
"status": "affected",
"version": "27c24fda62b601d6f9ca5e992502578c4310876f",
"lessThan": "d141d9b769bcd1b747898528c5023270cda040f2",
"versionType": "git"
},
{
"status": "affected",
"version": "27c24fda62b601d6f9ca5e992502578c4310876f",
"lessThan": "73cb063f5ec6ca51eb1e246c6d332563002ac277",
"versionType": "git"
},
{
"status": "affected",
"version": "27c24fda62b601d6f9ca5e992502578c4310876f",
"lessThan": "7199c78c3a3e399a4dc439d845826793880ccedc",
"versionType": "git"
},
{
"status": "affected",
"version": "27c24fda62b601d6f9ca5e992502578c4310876f",
"lessThan": "4e37f6452d586b95c346a9abdd2fb80b67794f39",
"versionType": "git"
}
],
"programFiles": [
"net/bluetooth/sco.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": "5.15.212",
"versionType": "semver",
"lessThanOrEqual": "5.15.*"
},
{
"status": "unaffected",
"version": "6.1.178",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.145",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.97",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.40",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.1",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"net/bluetooth/sco.c"
],
"defaultStatus": "affected"
}
]
}
],
"published": "2026-09-16T09:17:07.717",
"references": [
{
"url": "https://git.kernel.org/stable/c/4e37f6452d586b95c346a9abdd2fb80b67794f39",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/50aae396dc30377bec8e3b181b8346f8fd38f7d8",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/6e3840578aaad1a296aab1eaaa89ea3b7d5cbae1",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/7199c78c3a3e399a4dc439d845826793880ccedc",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/73cb063f5ec6ca51eb1e246c6d332563002ac277",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/d141d9b769bcd1b747898528c5023270cda040f2",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
],
"vulnStatus": "Received",
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: SCO: hold sk properly in sco_conn_ready\n\nsk deref in sco_conn_ready must be done either under conn->lock, or\nholding a refcount, to avoid concurrent close. conn->sk and parent sk is\ncurrently accessed without either, and without checking parent->sk_state:\n\n [Task 1] [Task 2]\n sco_sock_release\n sco_conn_ready\n sk = conn->sk\n lock_sock(sk)\n conn->sk = NULL\n lock_sock(sk)\n release_sock(sk)\n sco_sock_kill(sk)\n UAF on sk deref\n\nand similarly for access to sco_get_sock_listen() return value.\n\nFix possible UAF by holding sk refcount in sco_conn_ready() and making\nsco_get_sock_listen() increase refcount. Also recheck after lock_sock\nthat the socket is still valid. Adjust conn->sk locking so it's\nprotected also by lock_sock() of the associated socket if any."
}
],
"lastModified": "2026-09-16T15:18:06.747",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}