CVE-2026-98287
Estado: RecibidaSin puntuar—
In the Linux kernel, the following vulnerability has been resolved:
pppoatm: ensure a writable skb header and linear data
In pppoatm_send(), LLC encapsulation checks whether there is sufficient headroom for the 4-byte LLC header, but does not ensure that the skb header is writable.
Normal transmit packets passing through ppp_start_xmit() have their header unshared via skb_cow_head(). However, packets can also reach pppoatm_send() via PPP channel bridging (PPPIOCBRIDGECHAN) without going through ppp_start_xmit().
Use skb_cow_head() to ensure both sufficient headroom and a writable header before pushing the LLC header.
Detalles técnicos trazas, registros y código del informe original
While at it: - Call pskb_may_pull(skb, 1) before inspecting skb->data[0] to prevent out-of-bounds reads on zero-length or non-linear frames (e.g. from bridging). - Defer SC_COMP_PROT protocol compression until after pppoatm_may_send() succeeds. This eliminates the temporary skb allocation on admission failure and completely removes the fragile "undo" heuristic at the nospace label, avoiding any risk of reading uninitialized headroom or performing an unbalanced skb_push().
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: 0.18%
- Percentil entre todas las CVEs puntuadas: 7
- 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).
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/208ccc4d08b1897451e9ba01c016bf93ff107966
- https://git.kernel.org/stable/c/30992fe39e65589ed8e000425e088fa74994b811
- https://git.kernel.org/stable/c/8e66c5969acd859ba72fb0a7fa895623fc1b3769
- https://git.kernel.org/stable/c/e2f5529b0016db7d34f411408607f5cf395a542e
- https://git.kernel.org/stable/c/e6cd1bba7d113c15c00ac63671213a096fe4d686
- https://git.kernel.org/stable/c/ecc7253683a3c55caa868ce0ee530fcb0044bd3c
- https://git.kernel.org/stable/c/ffc448eb54f5ba80d4212c1e870cdb92b0f709fa
JSON original (NVD)
Mostrar
{
"id": "CVE-2026-98287",
"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": "4cf476ced45d7f12df30a68e833b263e7a2202d1",
"lessThan": "208ccc4d08b1897451e9ba01c016bf93ff107966",
"versionType": "git"
},
{
"status": "affected",
"version": "4cf476ced45d7f12df30a68e833b263e7a2202d1",
"lessThan": "e6cd1bba7d113c15c00ac63671213a096fe4d686",
"versionType": "git"
},
{
"status": "affected",
"version": "4cf476ced45d7f12df30a68e833b263e7a2202d1",
"lessThan": "ffc448eb54f5ba80d4212c1e870cdb92b0f709fa",
"versionType": "git"
},
{
"status": "affected",
"version": "4cf476ced45d7f12df30a68e833b263e7a2202d1",
"lessThan": "8e66c5969acd859ba72fb0a7fa895623fc1b3769",
"versionType": "git"
},
{
"status": "affected",
"version": "4cf476ced45d7f12df30a68e833b263e7a2202d1",
"lessThan": "e2f5529b0016db7d34f411408607f5cf395a542e",
"versionType": "git"
},
{
"status": "affected",
"version": "4cf476ced45d7f12df30a68e833b263e7a2202d1",
"lessThan": "30992fe39e65589ed8e000425e088fa74994b811",
"versionType": "git"
},
{
"status": "affected",
"version": "4cf476ced45d7f12df30a68e833b263e7a2202d1",
"lessThan": "ecc7253683a3c55caa868ce0ee530fcb0044bd3c",
"versionType": "git"
}
],
"programFiles": [
"net/atm/pppoatm.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "5.11"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "5.11",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "5.15.222",
"versionType": "semver",
"lessThanOrEqual": "5.15.*"
},
{
"status": "unaffected",
"version": "6.1.189",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.158",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.112",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.54",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.2.8",
"versionType": "semver",
"lessThanOrEqual": "7.2.*"
},
{
"status": "unaffected",
"version": "7.3-rc4",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"net/atm/pppoatm.c"
],
"defaultStatus": "affected"
}
]
}
],
"published": "2026-10-06T09:18:18.880",
"references": [
{
"url": "https://git.kernel.org/stable/c/208ccc4d08b1897451e9ba01c016bf93ff107966",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/30992fe39e65589ed8e000425e088fa74994b811",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/8e66c5969acd859ba72fb0a7fa895623fc1b3769",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/e2f5529b0016db7d34f411408607f5cf395a542e",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/e6cd1bba7d113c15c00ac63671213a096fe4d686",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/ecc7253683a3c55caa868ce0ee530fcb0044bd3c",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/ffc448eb54f5ba80d4212c1e870cdb92b0f709fa",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
],
"vulnStatus": "Received",
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\npppoatm: ensure a writable skb header and linear data\n\nIn pppoatm_send(), LLC encapsulation checks whether there is sufficient\nheadroom for the 4-byte LLC header, but does not ensure that the skb header\nis writable.\n\nNormal transmit packets passing through ppp_start_xmit() have their header\nunshared via skb_cow_head(). However, packets can also reach pppoatm_send()\nvia PPP channel bridging (PPPIOCBRIDGECHAN) without going through\nppp_start_xmit().\n\nUse skb_cow_head() to ensure both sufficient headroom and a writable\nheader before pushing the LLC header.\n\nWhile at it:\n- Call pskb_may_pull(skb, 1) before inspecting skb->data[0] to prevent\n out-of-bounds reads on zero-length or non-linear frames (e.g. from\n bridging).\n- Defer SC_COMP_PROT protocol compression until after pppoatm_may_send()\n succeeds. This eliminates the temporary skb allocation on admission failure\n and completely removes the fragile \"undo\" heuristic at the nospace label,\n avoiding any risk of reading uninitialized headroom or performing an\n unbalanced skb_push()."
}
],
"lastModified": "2026-10-06T09:18:18.880",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}