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CVE-2026-89471

Estado: RecibidaAlta (8.4)—

In the Linux kernel, the following vulnerability has been resolved:

power: supply: cros_usbpd-charger: bound the EC-reported port count

cros_usbpd_charger_probe() reads two port counts from the EC and uses one of them, num_charger_ports, as the loop bound when populating a fixed-size array:

Both num_usbpd_ports (from EC_CMD_USB_PD_PORTS) and num_charger_ports (from EC_CMD_CHARGE_PORT_COUNT) are u8 values reported by the EC. The only validation is a sanity check that compares the two EC-reported values against each other:

It never checks either count against EC_USB_PD_MAX_PORTS, the size of the ports[] array.

Leer descripción completaMostrar menos

A malfunctioning, malicious or compromised EC that reports num_usbpd_ports == num_charger_ports == N for any N > 8 (for example both 255) passes this check, and the loop then writes N pointers into the 8-entry ports[] array embedded in the devm_kzalloc()'d charger_data, overflowing it by up to 255 - 8 = 247 entries (~1976 bytes): a slab out-of-bounds write.

Reject a port count larger than the ports[] array can hold.

Detalles técnicos trazas, registros y código del informe original
	struct port_data *ports[EC_USB_PD_MAX_PORTS];	/* 8 entries */
	...
	for (i = 0; i < charger->num_charger_ports; i++)
		charger->ports[charger->num_registered_psy++] = port;

	if (num_charger_ports < num_usbpd_ports ||
	    num_charger_ports > num_usbpd_ports + 1)
		return -EPROTO;

CVSS

Probabilidad de explotación (EPSS)

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.

Vulnerabilidad de desbordamiento de buffer en kernel Linux (AV:L, acceso local sin interacción) que permite ejecutable en contexto de kernel. EC malicioso causa escritura fuera de límites en estructura de datos slab, permitiendo corrupción de memoria y negación de servicio.

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)

⚠ Inferidas por IA a partir de la descripción — NVD aún no ha analizado esta CVE; no son CPE verificados.

Referencias

JSON original (NVD)

Mostrar
{
  "id": "CVE-2026-89471",
  "cveTags": [],
  "metrics": {
    "cvssMetricV31": [
      {
        "type": "Secondary",
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "cvssData": {
          "scope": "UNCHANGED",
          "version": "3.1",
          "baseScore": 8.4,
          "attackVector": "LOCAL",
          "baseSeverity": "HIGH",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
          "integrityImpact": "HIGH",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "confidentialityImpact": "HIGH"
        },
        "impactScore": 5.9,
        "exploitabilityScore": 2.5
      }
    ]
  },
  "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": "f68b883e8fad23ed0ac4756d91594809d78678ed",
              "lessThan": "0b5096f6804161b61451b1cec0e38678630be849",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "f68b883e8fad23ed0ac4756d91594809d78678ed",
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              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "f68b883e8fad23ed0ac4756d91594809d78678ed",
              "lessThan": "a1905375dfc0b9612bbee52fc066e3a70c0d671d",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "f68b883e8fad23ed0ac4756d91594809d78678ed",
              "lessThan": "2746d502b12b343384fb747bdef9cbcfbd7444a2",
              "versionType": "git"
            },
            {
              "status": "affected",
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              "lessThan": "fd29d08ee487f3bf50f2575aaa74f78a74b09b21",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "f68b883e8fad23ed0ac4756d91594809d78678ed",
              "lessThan": "78be8b7403ff7638162438b664a07d19da76059e",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "f68b883e8fad23ed0ac4756d91594809d78678ed",
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              "versionType": "git"
            },
            {
              "status": "affected",
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              "lessThan": "48355ce49359740f52e94d3623f6fc557ce341f0",
              "versionType": "git"
            }
          ],
          "programFiles": [
            "drivers/power/supply/cros_usbpd-charger.c"
          ],
          "defaultStatus": "unaffected"
        },
        {
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "product": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "4.19"
            },
            {
              "status": "unaffected",
              "version": "0",
              "lessThan": "4.19",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "5.10.270",
              "versionType": "semver",
              "lessThanOrEqual": "5.10.*"
            },
            {
              "status": "unaffected",
              "version": "5.15.221",
              "versionType": "semver",
              "lessThanOrEqual": "5.15.*"
            },
            {
              "status": "unaffected",
              "version": "6.1.188",
              "versionType": "semver",
              "lessThanOrEqual": "6.1.*"
            },
            {
              "status": "unaffected",
              "version": "6.6.157",
              "versionType": "semver",
              "lessThanOrEqual": "6.6.*"
            },
            {
              "status": "unaffected",
              "version": "6.12.109",
              "versionType": "semver",
              "lessThanOrEqual": "6.12.*"
            },
            {
              "status": "unaffected",
              "version": "6.18.50",
              "versionType": "semver",
              "lessThanOrEqual": "6.18.*"
            },
            {
              "status": "unaffected",
              "version": "7.2.4",
              "versionType": "semver",
              "lessThanOrEqual": "7.2.*"
            },
            {
              "status": "unaffected",
              "version": "7.3-rc1",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ],
          "programFiles": [
            "drivers/power/supply/cros_usbpd-charger.c"
          ],
          "defaultStatus": "affected"
        }
      ]
    }
  ],
  "published": "2026-09-11T20:19:28.263",
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/0b5096f6804161b61451b1cec0e38678630be849",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/2746d502b12b343384fb747bdef9cbcfbd7444a2",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/3d1e01443b221081258ff34ea0cdd0431e4ff62e",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/48355ce49359740f52e94d3623f6fc557ce341f0",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/78be8b7403ff7638162438b664a07d19da76059e",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/a1905375dfc0b9612bbee52fc066e3a70c0d671d",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/c46c9f447415ca802afab51dea1eafc08ddff1c6",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/fd29d08ee487f3bf50f2575aaa74f78a74b09b21",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "vulnStatus": "Received",
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\npower: supply: cros_usbpd-charger: bound the EC-reported port count\n\ncros_usbpd_charger_probe() reads two port counts from the EC and uses\none of them, num_charger_ports, as the loop bound when populating a\nfixed-size array:\n\n\tstruct port_data *ports[EC_USB_PD_MAX_PORTS];\t/* 8 entries */\n\t...\n\tfor (i = 0; i < charger->num_charger_ports; i++)\n\t\tcharger->ports[charger->num_registered_psy++] = port;\n\nBoth num_usbpd_ports (from EC_CMD_USB_PD_PORTS) and num_charger_ports\n(from EC_CMD_CHARGE_PORT_COUNT) are u8 values reported by the EC. The\nonly validation is a sanity check that compares the two EC-reported\nvalues against each other:\n\n\tif (num_charger_ports < num_usbpd_ports ||\n\t    num_charger_ports > num_usbpd_ports + 1)\n\t\treturn -EPROTO;\n\nIt never checks either count against EC_USB_PD_MAX_PORTS, the size of\nthe ports[] array. A malfunctioning, malicious or compromised EC that\nreports num_usbpd_ports == num_charger_ports == N for any N > 8 (for\nexample both 255) passes this check, and the loop then writes N pointers\ninto the 8-entry ports[] array embedded in the devm_kzalloc()'d\ncharger_data, overflowing it by up to 255 - 8 = 247 entries (~1976\nbytes): a slab out-of-bounds write.\n\nReject a port count larger than the ports[] array can hold."
    }
  ],
  "lastModified": "2026-09-14T13:19:03.463",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}