CVE-2026-72393
In the Linux kernel, the following vulnerability has been resolved:
eth: fbnic: don't cache shinfo across skb realloc
fbnic_tx_lso() calls skb_cow_head() which may reallocate the skb including the shared info. We can't use the pointer calculated before the call.
Detalles técnicos trazas, registros y código del informe original
BUG: KASAN: slab-use-after-free in fbnic_tx_lso.isra.0+0x668/0x8e0
Read of size 4 at addr ff110000262edd98 by task swapper/5/0
Call Trace:
fbnic_tx_lso.isra.0+0x668/0x8e0
fbnic_xmit_frame+0x622/0xba0
dev_hard_start_xmit+0xf4/0x620
Allocated by task 8653:
__alloc_skb+0x11e/0x5f0
alloc_skb_with_frags+0xcc/0x6c0
sock_alloc_send_pskb+0x327/0x3f0
__ip_append_data+0x188b/0x47a0
ip_make_skb+0x24a/0x300
udp_sendmsg+0x14d2/0x21e0
Freed by task 0:
kfree+0x123/0x5a0
pskb_expand_head+0x36c/0xfa0
fbnic_tx_lso.isra.0+0x500/0x8e0
fbnic_xmit_frame+0x622/0xba0
dev_hard_start_xmit+0xf4/0x620
sch_direct_xmit+0x25b/0x1100
The buggy address belongs to the object at ff110000262edc40
which belongs to the cache skbuff_small_head of size 640
The buggy address is located 344 bytes inside of
freed 640-byte region [ff110000262edc40, ff110000262edeCVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Puntuación base: 9.8
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.63%
- Percentil entre todas las CVEs puntuadas: 49
- 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
T1190Exploit Public-Facing Applicationinitial access75 % - Impacto principal
T1499.004Application or System Exploitationimpact65 % - Impacto secundario
T1068Exploitation for Privilege Escalationprivilege escalation55 %
Vulnerabilidad remota en kernel Linux (AV:N, PR:N, UI:N) en controlador de red fbnic: uso después de liberación en LSO causa crash/DoS o potencialmente escalada de privilegios en contexto 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
JSON original (NVD)
Mostrar
{
"id": "CVE-2026-72393",
"cveTags": [],
"metrics": {
"cvssMetricV31": [
{
"type": "Secondary",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 9.8,
"attackVector": "NETWORK",
"baseSeverity": "CRITICAL",
"vectorString": "CVSS:3.1/AV:N/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": 3.9
}
]
},
"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": "b0b0f52042acb324cd39fbefb2b1ae83af8f8ae1",
"lessThan": "83df3e2594cd78aa40b1246a19879abb4891945b",
"versionType": "git"
},
{
"status": "affected",
"version": "b0b0f52042acb324cd39fbefb2b1ae83af8f8ae1",
"lessThan": "21f304c2aae46625e050c28d979f4b9d83faa85e",
"versionType": "git"
},
{
"status": "affected",
"version": "b0b0f52042acb324cd39fbefb2b1ae83af8f8ae1",
"lessThan": "62b68b774f06bf52e329f254f0199bc43d350ccf",
"versionType": "git"
}
],
"programFiles": [
"drivers/net/ethernet/meta/fbnic/fbnic_txrx.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "6.15"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "6.15",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.18.40",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.1.5",
"versionType": "semver",
"lessThanOrEqual": "7.1.*"
},
{
"status": "unaffected",
"version": "7.2",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"drivers/net/ethernet/meta/fbnic/fbnic_txrx.c"
],
"defaultStatus": "affected"
}
]
}
],
"published": "2026-08-15T06:22:12.847",
"references": [
{
"url": "https://git.kernel.org/stable/c/21f304c2aae46625e050c28d979f4b9d83faa85e",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/62b68b774f06bf52e329f254f0199bc43d350ccf",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/83df3e2594cd78aa40b1246a19879abb4891945b",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
],
"vulnStatus": "Received",
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\neth: fbnic: don't cache shinfo across skb realloc\n\nfbnic_tx_lso() calls skb_cow_head() which may reallocate the skb\nincluding the shared info. We can't use the pointer calculated\nbefore the call.\n\n BUG: KASAN: slab-use-after-free in fbnic_tx_lso.isra.0+0x668/0x8e0\n Read of size 4 at addr ff110000262edd98 by task swapper/5/0\n Call Trace:\n fbnic_tx_lso.isra.0+0x668/0x8e0\n fbnic_xmit_frame+0x622/0xba0\n dev_hard_start_xmit+0xf4/0x620\n\n Allocated by task 8653:\n __alloc_skb+0x11e/0x5f0\n alloc_skb_with_frags+0xcc/0x6c0\n sock_alloc_send_pskb+0x327/0x3f0\n __ip_append_data+0x188b/0x47a0\n ip_make_skb+0x24a/0x300\n udp_sendmsg+0x14d2/0x21e0\n\n Freed by task 0:\n kfree+0x123/0x5a0\n pskb_expand_head+0x36c/0xfa0\n fbnic_tx_lso.isra.0+0x500/0x8e0\n fbnic_xmit_frame+0x622/0xba0\n dev_hard_start_xmit+0xf4/0x620\n sch_direct_xmit+0x25b/0x1100\n\n The buggy address belongs to the object at ff110000262edc40\n which belongs to the cache skbuff_small_head of size 640\n The buggy address is located 344 bytes inside of\n freed 640-byte region [ff110000262edc40, ff110000262ede"
}
],
"lastModified": "2026-08-17T06:19:05.793",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}