CVE-2026-53194
In the Linux kernel, the following vulnerability has been resolved:
USB: serial: kl5kusb105: fix bulk-out buffer overflow
klsi_105_prepare_write_buffer() is called by the generic write path with the bulk-out buffer and its size (bulk_out_size, 64 bytes). It stores a two-byte length header at the start of the buffer and copies the payload from the write fifo starting at buf + KLSI_HDR_LEN, but passes the full buffer size as the number of bytes to copy:
When the fifo holds at least size bytes, size bytes are copied starting two bytes into the size-byte buffer, writing KLSI_HDR_LEN bytes past its end. Copy at most size - KLSI_HDR_LEN bytes instead, leaving room for the header as safe_serial already does.
Leer descripción completaMostrar menos
Writing bulk_out_size or more bytes to the tty triggers a slab out-of-bounds write, observed with KASAN by emulating the device with dummy_hcd and raw-gadget:
The out-of-bounds write no longer occurs with this change applied.
Detalles técnicos trazas, registros y código del informe original
count = kfifo_out_locked(&port->write_fifo, buf + KLSI_HDR_LEN,
size, &port->lock);
BUG: KASAN: slab-out-of-bounds in kfifo_copy_out+0x83/0xc0
Write of size 64 at addr ffff888112c62202 by task python3
kfifo_copy_out
klsi_105_prepare_write_buffer [kl5kusb105]
usb_serial_generic_write_start [usbserial]
Allocated by task 139:
usb_serial_probe [usbserial]
The buggy address is located 2 bytes inside of allocated 64-byte regionCVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- Puntuación base: 7.8
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.15%
- Percentil entre todas las CVEs puntuadas: 3
- 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 escalation85 % - Impacto principal
T1059Command and Scripting Interpreterexecution75 %
Vulnerabilidad local de buffer overflow (CWE-787) con AV:L y PR:L en kernel de Linux; permite escalada de privilegios escribiendo fuera de límites. Impacto: ejecución de código con privilegios elevados.
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-787
- CWE-787
Referencias
- https://git.kernel.org/stable/c/0a57320f71941d4e0b1307453c9a1f0939afe666
- https://git.kernel.org/stable/c/14147b7963685957839c76ba8094924e22777d79
- https://git.kernel.org/stable/c/372f33ebed747d91870f57c0a2e62884a870bffa
- https://git.kernel.org/stable/c/60af1fd82983c26604102e63a3fcc822c186cceb
- https://git.kernel.org/stable/c/70d86e355c564b5510fde61361df014f5476c83e
- https://git.kernel.org/stable/c/96d47e40bf9db4a9efd5c8fb53287a508d165f14
- https://git.kernel.org/stable/c/a1288cd700f721c1a119c4f1e8efa234e59caada
- https://git.kernel.org/stable/c/bde742b076cbe26ecc89c8c68c76ae076a524d02
- https://access.redhat.com/security/cve/CVE-2026-53194
- https://bugzilla.redhat.com/show_bug.cgi?id=2492703
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-53194.json
JSON original (NVD)
Mostrar
{
"id": "CVE-2026-53194",
"cveTags": [],
"metrics": {
"cvssMetricV31": [
{
"type": "Secondary",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 7.8,
"attackVector": "LOCAL",
"baseSeverity": "HIGH",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"integrityImpact": "HIGH",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"availabilityImpact": "HIGH",
"privilegesRequired": "LOW",
"confidentialityImpact": "HIGH"
},
"impactScore": 5.9,
"exploitabilityScore": 1.8
},
{
"type": "Secondary",
"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 5.3,
"attackVector": "LOCAL",
"baseSeverity": "MEDIUM",
"vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:H",
"integrityImpact": "LOW",
"userInteraction": "NONE",
"attackComplexity": "HIGH",
"availabilityImpact": "HIGH",
"privilegesRequired": "LOW",
"confidentialityImpact": "NONE"
},
"impactScore": 4.2,
"exploitabilityScore": 1
}
]
},
"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": "60b3013cdaf3fa8a17243ca46b19db3cbe08d943",
"lessThan": "60af1fd82983c26604102e63a3fcc822c186cceb",
"versionType": "git"
},
{
"status": "affected",
"version": "60b3013cdaf3fa8a17243ca46b19db3cbe08d943",
"lessThan": "0a57320f71941d4e0b1307453c9a1f0939afe666",
"versionType": "git"
},
{
"status": "affected",
"version": "60b3013cdaf3fa8a17243ca46b19db3cbe08d943",
"lessThan": "14147b7963685957839c76ba8094924e22777d79",
"versionType": "git"
},
{
"status": "affected",
"version": "60b3013cdaf3fa8a17243ca46b19db3cbe08d943",
"lessThan": "a1288cd700f721c1a119c4f1e8efa234e59caada",
"versionType": "git"
},
{
"status": "affected",
"version": "60b3013cdaf3fa8a17243ca46b19db3cbe08d943",
"lessThan": "70d86e355c564b5510fde61361df014f5476c83e",
"versionType": "git"
},
{
"status": "affected",
"version": "60b3013cdaf3fa8a17243ca46b19db3cbe08d943",
"lessThan": "372f33ebed747d91870f57c0a2e62884a870bffa",
"versionType": "git"
},
{
"status": "affected",
"version": "60b3013cdaf3fa8a17243ca46b19db3cbe08d943",
"lessThan": "bde742b076cbe26ecc89c8c68c76ae076a524d02",
"versionType": "git"
},
{
"status": "affected",
"version": "60b3013cdaf3fa8a17243ca46b19db3cbe08d943",
"lessThan": "96d47e40bf9db4a9efd5c8fb53287a508d165f14",
"versionType": "git"
}
],
"programFiles": [
"drivers/usb/serial/kl5kusb105.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "2.6.35"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "2.6.35",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "5.10.259",
"versionType": "semver",
"lessThanOrEqual": "5.10.*"
},
{
"status": "unaffected",
"version": "5.15.210",
"versionType": "semver",
"lessThanOrEqual": "5.15.*"
},
{
"status": "unaffected",
"version": "6.1.176",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.143",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.94",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.36",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.0.13",
"versionType": "semver",
"lessThanOrEqual": "7.0.*"
},
{
"status": "unaffected",
"version": "7.1",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"drivers/usb/serial/kl5kusb105.c"
],
"defaultStatus": "affected"
}
]
},
{
"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c",
"affectedData": [
{
"cpes": [
"cpe:/o:redhat:enterprise_linux:10"
],
"vendor": "Red Hat",
"product": "Red Hat Enterprise Linux 10",
"packageName": "kernel",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"defaultStatus": "affected"
},
{
"cpes": [
"cpe:/o:redhat:enterprise_linux:6"
],
"vendor": "Red Hat",
"product": "Red Hat Enterprise Linux 6",
"packageName": "kernel",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"defaultStatus": "unaffected"
},
{
"cpes": [
"cpe:/o:redhat:enterprise_linux:7"
],
"vendor": "Red Hat",
"product": "Red Hat Enterprise Linux 7",
"packageName": "kernel",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"defaultStatus": "affected"
},
{
"cpes": [
"cpe:/o:redhat:enterprise_linux:7"
],
"vendor": "Red Hat",
"product": "Red Hat Enterprise Linux 7",
"packageName": "kernel-rt",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"defaultStatus": "affected"
},
{
"cpes": [
"cpe:/o:redhat:enterprise_linux:8"
],
"vendor": "Red Hat",
"product": "Red Hat Enterprise Linux 8",
"packageName": "kernel",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"defaultStatus": "affected"
},
{
"cpes": [
"cpe:/o:redhat:enterprise_linux:8"
],
"vendor": "Red Hat",
"product": "Red Hat Enterprise Linux 8",
"packageName": "kernel-rt",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"defaultStatus": "affected"
},
{
"cpes": [
"cpe:/o:redhat:enterprise_linux:9"
],
"vendor": "Red Hat",
"product": "Red Hat Enterprise Linux 9",
"packageName": "kernel",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"defaultStatus": "affected"
},
{
"cpes": [
"cpe:/o:redhat:enterprise_linux:9"
],
"vendor": "Red Hat",
"product": "Red Hat Enterprise Linux 9",
"packageName": "kernel-rt",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"defaultStatus": "affected"
}
]
}
],
"published": "2026-06-25T09:16:36.850",
"references": [
{
"url": "https://git.kernel.org/stable/c/0a57320f71941d4e0b1307453c9a1f0939afe666",
"tags": [
"Patch"
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/14147b7963685957839c76ba8094924e22777d79",
"tags": [
"Patch"
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/372f33ebed747d91870f57c0a2e62884a870bffa",
"tags": [
"Patch"
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/60af1fd82983c26604102e63a3fcc822c186cceb",
"tags": [
"Patch"
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/70d86e355c564b5510fde61361df014f5476c83e",
"tags": [
"Patch"
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/96d47e40bf9db4a9efd5c8fb53287a508d165f14",
"tags": [
"Patch"
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/a1288cd700f721c1a119c4f1e8efa234e59caada",
"tags": [
"Patch"
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/bde742b076cbe26ecc89c8c68c76ae076a524d02",
"tags": [
"Patch"
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://access.redhat.com/security/cve/CVE-2026-53194",
"tags": [
"Third Party Advisory"
],
"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"
},
{
"url": "https://bugzilla.redhat.com/show_bug.cgi?id=2492703",
"tags": [
"Issue Tracking",
"Third Party Advisory"
],
"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"
},
{
"url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-53194.json",
"tags": [
"Third Party Advisory"
],
"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"
}
],
"vulnStatus": "Analyzed",
"weaknesses": [
{
"type": "Primary",
"source": "nvd@nist.gov",
"description": [
{
"lang": "en",
"value": "CWE-787"
}
]
},
{
"type": "Secondary",
"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c",
"description": [
{
"lang": "en",
"value": "CWE-787"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nUSB: serial: kl5kusb105: fix bulk-out buffer overflow\n\nklsi_105_prepare_write_buffer() is called by the generic write path\nwith the bulk-out buffer and its size (bulk_out_size, 64 bytes). It\nstores a two-byte length header at the start of the buffer and copies\nthe payload from the write fifo starting at buf + KLSI_HDR_LEN, but\npasses the full buffer size as the number of bytes to copy:\n\n count = kfifo_out_locked(&port->write_fifo, buf + KLSI_HDR_LEN,\n size, &port->lock);\n\nWhen the fifo holds at least size bytes, size bytes are copied starting\ntwo bytes into the size-byte buffer, writing KLSI_HDR_LEN bytes past its\nend. Copy at most size - KLSI_HDR_LEN bytes instead, leaving room for\nthe header as safe_serial already does.\n\nWriting bulk_out_size or more bytes to the tty triggers a slab\nout-of-bounds write, observed with KASAN by emulating the device with\ndummy_hcd and raw-gadget:\n\n BUG: KASAN: slab-out-of-bounds in kfifo_copy_out+0x83/0xc0\n Write of size 64 at addr ffff888112c62202 by task python3\n kfifo_copy_out\n klsi_105_prepare_write_buffer [kl5kusb105]\n usb_serial_generic_write_start [usbserial]\n Allocated by task 139:\n usb_serial_probe [usbserial]\n The buggy address is located 2 bytes inside of allocated 64-byte region\n\nThe out-of-bounds write no longer occurs with this change applied."
}
],
"lastModified": "2026-07-15T01:16:30.943",
"configurations": [
{
"nodes": [
{
"negate": false,
"cpeMatch": [
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "7CB9160D-1913-428C-A99E-1DAF6FCF44A7",
"versionEndExcluding": "5.10.259",
"versionStartIncluding": "2.6.35"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "5E938CDF-D1C4-43D0-98DC-9E11B6B55801",
"versionEndExcluding": "5.15.210",
"versionStartIncluding": "5.11"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "C4446623-5F2B-4DD8-8666-9FAAC285A757",
"versionEndExcluding": "6.1.176",
"versionStartIncluding": "5.16"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "9062F1CD-CAD6-4EA2-A73F-C06D4A887B8C",
"versionEndExcluding": "6.6.143",
"versionStartIncluding": "6.2"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "85421C0C-ABDE-4357-971C-67F9087DE1B9",
"versionEndExcluding": "6.12.94",
"versionStartIncluding": "6.7"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "389025D2-958D-41BD-BD96-70ED1033A9F3",
"versionEndExcluding": "6.18.36",
"versionStartIncluding": "6.13"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "6A64BF9F-3BCA-42FD-98CB-8F03474D2B1E",
"versionEndExcluding": "7.0.13",
"versionStartIncluding": "6.19"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc1:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "B1EF7059-E670-45F4-B422-54C40FA86390"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc2:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "0D38F0BF-A728-4133-A358-D44A2F7EE6D6"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc3:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "EC732D08-5F7B-46D9-B154-E60C7F4F0A97"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc4:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "E5910A9D-F60A-409A-B486-FE66BFEBA9B9"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc5:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "81DFF19E-9CF8-49C6-8C36-1E4038622933"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc6:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "B0E8FC71-3952-444C-83E9-718DBBBEC615"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc7:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "1039E95A-8CC3-4C88-8FF9-5C08EEB861C9"
}
],
"operator": "OR"
}
]
}
],
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}