CVE-2026-64121
In the Linux kernel, the following vulnerability has been resolved:
net: ifb: report ethtool stats over num_tx_queues
ifb_dev_init() allocates dp->tx_private to dev->num_tx_queues entries via kzalloc_objs(*txp, dev->num_tx_queues). Both IFB per-queue RX and TX stats live in those entries: ifb_xmit() updates txp->rx_stats using the skb queue mapping, ifb_ri_tasklet() updates txp->tx_stats, and ifb_stats64() aggregates both over dev->num_tx_queues.
The ethtool stats callbacks instead size and walk the per-queue stats with dev->real_num_rx_queues and dev->real_num_tx_queues. With an asymmetric device where the RX queue count exceeds the TX queue count, for example:
Leer descripción completaMostrar menos
ifb_get_ethtool_stats() indexes past the tx_private allocation and copies adjacent slab data through ETHTOOL_GSTATS.
Use dev->num_tx_queues consistently for the stats strings, the stats count, and the stats data walks. This reports one RX stats group and one TX stats group for each backing ifb_q_private entry, which is the queue set IFB can actually populate.
Reproduced under UML+KASAN at v7.1-rc2:
With the patch applied, the same UML+KASAN repro is silent and ethtool -S ifb10 reports only the stats backed by the single allocated tx_private entry.
Detalles técnicos trazas, registros y código del informe original
ip link add name ifb10 numtxqueues 1 numrxqueues 8 type ifb
ethtool -S ifb10
BUG: KASAN: slab-out-of-bounds in ifb_fill_stats_data+0x3c/0xae
Read of size 8 at addr 0000000062dbd228 by task ethtool/36
ifb_fill_stats_data+0x3c/0xae
ifb_get_ethtool_stats+0xc0/0x129
__dev_ethtool+0x1ca5/0x363c
dev_ethtool+0x123/0x1b3
dev_ioctl+0x56c/0x744
sock_do_ioctl+0x15f/0x1b2
sock_ioctl+0x4d5/0x50a
sys_ioctl+0xd8b/0xde9CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
- Puntuación base: 7.1
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: 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 escalation75 % - Impacto principal
T1005Data from Local Systemcollection65 % - Impacto secundario
T1499.004Application or System Exploitationimpact55 %
CVE con AV:L/PR:L (acceso local sin interacción) se clasifica como T1068. El desbordamiento de búfer (CWE-125) en el kernel permite lectura de memoria adyacente (T1005) y potencial DoS por corrupción (T1499.004).
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)
CWE
- CWE-125
Referencias
- https://git.kernel.org/stable/c/16bd798cb6d8337d7c3eea1adc412f31b5181d5b
- https://git.kernel.org/stable/c/2638e1773904d7aa8f24c6e7fda2ed7d69df6fa4
- https://git.kernel.org/stable/c/301a554e458e2f5ec47f2c336a7cb03b877f9fd6
- https://git.kernel.org/stable/c/5db89c99566fc4728cc92e941d8e1975711e24b5
- https://git.kernel.org/stable/c/6afdb8113cb007f9332f59a9b7fd45731b8a9de5
- https://git.kernel.org/stable/c/f8a5a76b4a683043c6eff2a060bcaa17f9316ad5
JSON original (NVD)
Mostrar
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"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: ifb: report ethtool stats over num_tx_queues\n\nifb_dev_init() allocates dp->tx_private to dev->num_tx_queues\nentries via kzalloc_objs(*txp, dev->num_tx_queues). Both IFB\nper-queue RX and TX stats live in those entries: ifb_xmit() updates\ntxp->rx_stats using the skb queue mapping, ifb_ri_tasklet() updates\ntxp->tx_stats, and ifb_stats64() aggregates both over\ndev->num_tx_queues.\n\nThe ethtool stats callbacks instead size and walk the per-queue\nstats with dev->real_num_rx_queues and dev->real_num_tx_queues. With\nan asymmetric device where the RX queue count exceeds the TX queue\ncount, for example:\n\n ip link add name ifb10 numtxqueues 1 numrxqueues 8 type ifb\n ethtool -S ifb10\n\nifb_get_ethtool_stats() indexes past the tx_private allocation and\ncopies adjacent slab data through ETHTOOL_GSTATS.\n\nUse dev->num_tx_queues consistently for the stats strings, the\nstats count, and the stats data walks. This reports one RX stats\ngroup and one TX stats group for each backing ifb_q_private entry,\nwhich is the queue set IFB can actually populate.\n\nReproduced under UML+KASAN at v7.1-rc2:\n\n BUG: KASAN: slab-out-of-bounds in ifb_fill_stats_data+0x3c/0xae\n Read of size 8 at addr 0000000062dbd228 by task ethtool/36\n ifb_fill_stats_data+0x3c/0xae\n ifb_get_ethtool_stats+0xc0/0x129\n __dev_ethtool+0x1ca5/0x363c\n dev_ethtool+0x123/0x1b3\n dev_ioctl+0x56c/0x744\n sock_do_ioctl+0x15f/0x1b2\n sock_ioctl+0x4d5/0x50a\n sys_ioctl+0xd8b/0xde9\n\nWith the patch applied, the same UML+KASAN repro is silent and\nethtool -S ifb10 reports only the stats backed by the single\nallocated tx_private entry."
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"lastModified": "2026-08-13T15:11:43.200",
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