CVE-2026-93783
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: RFCOMM: validate skb length in rfcomm_recv_frame
rfcomm_recv_frame() casts skb->data to struct rfcomm_hdr and dereferences hdr->addr and hdr->ctrl without validating skb->len first. A truncated frame with skb->len less than the minimum header size causes an out-of-bounds read of uninitialized memory. Additionally, a zero-length frame causes skb->len-- to underflow to UINT_MAX, making skb_tail_pointer() read far past the buffer.
Commit 23882b828c3c ("Bluetooth: RFCOMM: validate skb length in MCC handlers") fixed the same class of missing-length-check bugs in the MCC sub-handlers, but the top-level rfcomm_recv_frame() was left unfixed. KMSAN reports:
Leer descripción completaMostrar menos
Fix this by rejecting frames smaller than sizeof(struct rfcomm_hdr) + 1 (the minimum frame must have a 3-byte header and a 1-byte FCS).
Detalles técnicos trazas, registros y código del informe original
BUG: KMSAN: uninit-value in rfcomm_run
...
Uninit was created at:
__alloc_skb+0x474/0xb60
vhci_write+0xe9/0x870CVSS
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: 6
- 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/30d1d9f3495463f7c026e4c553127f79b486fcd6
- https://git.kernel.org/stable/c/3829af5fab5a22405bf1e7d69068c2ec0fce46ca
- https://git.kernel.org/stable/c/67dc3b40fae71b6b11c71e7ff69bac0758818c05
- https://git.kernel.org/stable/c/b161eacd7fa4a2d765724b5504ac6cc388e48f80
- https://git.kernel.org/stable/c/b230e5bf501c5edaf2eb0991cb862ac142031d4b
- https://git.kernel.org/stable/c/bbc310caa2b6bf5fe42896ba27da0fbc12e4ac51
- https://git.kernel.org/stable/c/fb40eda15122f6b780228639c1ead6820340ff54
JSON original (NVD)
Mostrar
{
"id": "CVE-2026-93783",
"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": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
"lessThan": "fb40eda15122f6b780228639c1ead6820340ff54",
"versionType": "git"
},
{
"status": "affected",
"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
"lessThan": "3829af5fab5a22405bf1e7d69068c2ec0fce46ca",
"versionType": "git"
},
{
"status": "affected",
"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
"lessThan": "b161eacd7fa4a2d765724b5504ac6cc388e48f80",
"versionType": "git"
},
{
"status": "affected",
"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
"lessThan": "30d1d9f3495463f7c026e4c553127f79b486fcd6",
"versionType": "git"
},
{
"status": "affected",
"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
"lessThan": "67dc3b40fae71b6b11c71e7ff69bac0758818c05",
"versionType": "git"
},
{
"status": "affected",
"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
"lessThan": "bbc310caa2b6bf5fe42896ba27da0fbc12e4ac51",
"versionType": "git"
},
{
"status": "affected",
"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
"lessThan": "b230e5bf501c5edaf2eb0991cb862ac142031d4b",
"versionType": "git"
}
],
"programFiles": [
"net/bluetooth/rfcomm/core.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "2.6.12"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "2.6.12",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "5.10.271",
"versionType": "semver",
"lessThanOrEqual": "5.10.*"
},
{
"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": "6.12.111",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.53",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.2",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"net/bluetooth/rfcomm/core.c"
],
"defaultStatus": "affected"
}
]
}
],
"published": "2026-09-24T17:17:10.907",
"references": [
{
"url": "https://git.kernel.org/stable/c/30d1d9f3495463f7c026e4c553127f79b486fcd6",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/3829af5fab5a22405bf1e7d69068c2ec0fce46ca",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/67dc3b40fae71b6b11c71e7ff69bac0758818c05",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/b161eacd7fa4a2d765724b5504ac6cc388e48f80",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/b230e5bf501c5edaf2eb0991cb862ac142031d4b",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/bbc310caa2b6bf5fe42896ba27da0fbc12e4ac51",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/fb40eda15122f6b780228639c1ead6820340ff54",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
],
"vulnStatus": "Received",
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: RFCOMM: validate skb length in rfcomm_recv_frame\n\nrfcomm_recv_frame() casts skb->data to struct rfcomm_hdr and dereferences\nhdr->addr and hdr->ctrl without validating skb->len first. A truncated\nframe with skb->len less than the minimum header size causes an\nout-of-bounds read of uninitialized memory. Additionally, a zero-length\nframe causes skb->len-- to underflow to UINT_MAX, making\nskb_tail_pointer() read far past the buffer.\n\nCommit 23882b828c3c (\"Bluetooth: RFCOMM: validate skb length in MCC\nhandlers\") fixed the same class of missing-length-check bugs in the MCC\nsub-handlers, but the top-level rfcomm_recv_frame() was left unfixed.\nKMSAN reports:\n\n BUG: KMSAN: uninit-value in rfcomm_run\n ...\n Uninit was created at:\n __alloc_skb+0x474/0xb60\n vhci_write+0xe9/0x870\n\nFix this by rejecting frames smaller than sizeof(struct rfcomm_hdr) + 1\n(the minimum frame must have a 3-byte header and a 1-byte FCS)."
}
],
"lastModified": "2026-10-03T11:17:47.810",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}