CVE-2026-80825
In the Linux kernel, the following vulnerability has been resolved:
wifi: mt76: mt7925: ensure tx headroom in usb_sdio_tx_prepare_skb
mt7925_usb_sdio_tx_prepare_skb() pushes a TX descriptor and a USB header onto every skb and assumes the headroom for them is already there. That holds for locally generated traffic, where mac80211 reserves hw->extra_tx_headroom, but forwarded frames are sent through ieee80211_8023_xmit(), which does not reserve it. Bridge a wired interface to an mt7925u AP and the first forwarded frame that arrives short panics the kernel:
Whether a given setup hits it depends on how much headroom the ingress netdev leaves in its rx skbs.
Leer descripción completaMostrar menos
Reproduced on a Raspberry Pi 5 bridging onboard ethernet to a Netgear A9000; originally reported on an MT7986 router running OpenWrt. Nick Morrow's testing on a Pi 4 (bcmgenet), which leaves more headroom, helped narrow the trigger to the ingress path.
The same bug was fixed on mt7921 by commit 98c4d0abf5c4 ("mt76: mt7921: don't assume adequate headroom for SDIO headers"), but mt7925 was copied from mt7921 without the fix. Add the same guard here.
Detalles técnicos trazas, registros y código del informe original
skbuff: skb_under_panic: len:415 put:4 tail:0x19b end:0x640 dev:wlan1 kernel BUG at net/core/skbuff.c:212! Call trace: skb_panic+0x58/0x60 (P) skb_push+0x58/0x60 mt7925_usb_sdio_tx_prepare_skb+0xf8/0x1b8 [mt7925_common] mt76u_tx_queue_skb+0xa0/0x1f8 [mt76_usb] __mt76_tx_queue_skb+0x54/0xe8 [mt76] mt76_txq_schedule.part.0+0x204/0x478 [mt76] mt76_txq_schedule_all+0x50/0x80 [mt76] mt792x_tx_worker+0x68/0x100 [mt792x_lib] __mt76_worker_fn+0x84/0x150 [mt76]
CVSS
NVD no ha asignado puntuación CVSS a esta CVE (habitual desde el cambio de política de abril de 2026).
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.17%
- Percentil entre todas las CVEs puntuadas: 5
- 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).
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/22edb6786127271aeba7abd30f152977c605c6a3
- https://git.kernel.org/stable/c/8d481f93588932a95f657671d4e1601b90d130cc
- https://git.kernel.org/stable/c/9a72b180f0575e41471e088e09bddc4b73d6dee2
- https://git.kernel.org/stable/c/e5e8fc11a7ac578f16079f855b7fffc1649d053c
- https://git.kernel.org/stable/c/ef3e34874d2332d0f63e72c2c35ce5c93568c125
JSON original (NVD)
Mostrar
{
"id": "CVE-2026-80825",
"cveTags": [],
"metrics": {},
"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": "c948b5da6bbec742b433138e3e3f9537a85af2e5",
"lessThan": "9a72b180f0575e41471e088e09bddc4b73d6dee2",
"versionType": "git"
},
{
"status": "affected",
"version": "c948b5da6bbec742b433138e3e3f9537a85af2e5",
"lessThan": "22edb6786127271aeba7abd30f152977c605c6a3",
"versionType": "git"
},
{
"status": "affected",
"version": "c948b5da6bbec742b433138e3e3f9537a85af2e5",
"lessThan": "8d481f93588932a95f657671d4e1601b90d130cc",
"versionType": "git"
},
{
"status": "affected",
"version": "c948b5da6bbec742b433138e3e3f9537a85af2e5",
"lessThan": "e5e8fc11a7ac578f16079f855b7fffc1649d053c",
"versionType": "git"
},
{
"status": "affected",
"version": "c948b5da6bbec742b433138e3e3f9537a85af2e5",
"lessThan": "ef3e34874d2332d0f63e72c2c35ce5c93568c125",
"versionType": "git"
}
],
"programFiles": [
"drivers/net/wireless/mediatek/mt76/mt7925/mac.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "6.7"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "6.7",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.12.108",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.49",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.1.13",
"versionType": "semver",
"lessThanOrEqual": "7.1.*"
},
{
"status": "unaffected",
"version": "7.2.3",
"versionType": "semver",
"lessThanOrEqual": "7.2.*"
},
{
"status": "unaffected",
"version": "7.3-rc1",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"drivers/net/wireless/mediatek/mt76/mt7925/mac.c"
],
"defaultStatus": "affected"
}
]
}
],
"published": "2026-09-04T16:18:10.410",
"references": [
{
"url": "https://git.kernel.org/stable/c/22edb6786127271aeba7abd30f152977c605c6a3",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/8d481f93588932a95f657671d4e1601b90d130cc",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/9a72b180f0575e41471e088e09bddc4b73d6dee2",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/e5e8fc11a7ac578f16079f855b7fffc1649d053c",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/ef3e34874d2332d0f63e72c2c35ce5c93568c125",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
],
"vulnStatus": "Received",
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nwifi: mt76: mt7925: ensure tx headroom in usb_sdio_tx_prepare_skb\n\nmt7925_usb_sdio_tx_prepare_skb() pushes a TX descriptor and a USB\nheader onto every skb and assumes the headroom for them is already\nthere. That holds for locally generated traffic, where mac80211\nreserves hw->extra_tx_headroom, but forwarded frames are sent through\nieee80211_8023_xmit(), which does not reserve it. Bridge a wired\ninterface to an mt7925u AP and the first forwarded frame that arrives\nshort panics the kernel:\n\n skbuff: skb_under_panic: len:415 put:4 tail:0x19b end:0x640 dev:wlan1\n kernel BUG at net/core/skbuff.c:212!\n Call trace:\n skb_panic+0x58/0x60 (P)\n skb_push+0x58/0x60\n mt7925_usb_sdio_tx_prepare_skb+0xf8/0x1b8 [mt7925_common]\n mt76u_tx_queue_skb+0xa0/0x1f8 [mt76_usb]\n __mt76_tx_queue_skb+0x54/0xe8 [mt76]\n mt76_txq_schedule.part.0+0x204/0x478 [mt76]\n mt76_txq_schedule_all+0x50/0x80 [mt76]\n mt792x_tx_worker+0x68/0x100 [mt792x_lib]\n __mt76_worker_fn+0x84/0x150 [mt76]\n\nWhether a given setup hits it depends on how much headroom the ingress\nnetdev leaves in its rx skbs. Reproduced on a Raspberry Pi 5 bridging\nonboard ethernet to a Netgear A9000; originally reported on an MT7986\nrouter running OpenWrt. Nick Morrow's testing on a Pi 4 (bcmgenet),\nwhich leaves more headroom, helped narrow the trigger to the ingress\npath.\n\nThe same bug was fixed on mt7921 by commit 98c4d0abf5c4 (\"mt76:\nmt7921: don't assume adequate headroom for SDIO headers\"), but mt7925\nwas copied from mt7921 without the fix. Add the same guard here."
}
],
"lastModified": "2026-09-04T16:18:10.410",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}