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CVE-2026-19576

Full vulnerability record from the local CVENow database.

Description

The Goodix GT9xx input driver in drivers/input/input_gt911.c reads the touch point count from the controller's status register and masks it with GT911_TOUCH_POINTS_MSK (0x0F), yielding a value of 0..15. In gt911_process() that value is used directly as the loop bound for filling point_reg[], a stack array sized to CONFIG_INPUT_GT911_MAX_TOUCH_POINTS, whose Kconfig range is 1..5 with a default of 1. No other check constrains the count; the driver relied only on a comment asserting that the controller had been programmed at init to report no more points than configured. Each loop iteration issues an I2C read of eight bytes straight into point_reg[i], so a controller that reports more points than the array holds causes up to 112 bytes of peer-supplied data to be written past the end of the array, over the stack frame of gt911_process() in the system workqueue thread. Two further loops then read out of bounds from the same array. Triggering it requires control of, or the ability to substitute, the I2C touch controller — plausible on the many supported boards where the GT9xx panel is a pluggable display module or shield rather than an on-PCB part; a spoofed device need only answer the init probes with a supported product ID and a checksum-valid config blob. The same overflow can also occur non-adversarially, with a GT9271-class panel that ignores the driver's touch-count programming and reports up to ten points, or with bus corruption of the single status byte. The impact is an out-of-bounds stack write with fully attacker-chosen content executing at kernel privilege, i.e. potential control-flow hijack on the host MCU, in addition to out-of-bounds reads and crashes. The attack vector is physical/local hardware access only; there is no network, USB, or syscall path to the defect. The fix clamps the reported count with min() against CONFIG_INPUT_GT911_MAX_TOUCH_POINTS before any array indexing.

Severity
MEDIUM
CVSS score
6.8 (v3.1)
Vulnerability status
Awaiting Analysis
Source identifier
Published
2026-10-11 18:16:58.300000
Last modified
2026-11-04 05:18:49.190000
View original CVE JSON
{
  "id": "CVE-2026-19576",
  "sourceIdentifier": "[email protected]",
  "published": "2026-10-11T18:16:58.300",
  "lastModified": "2026-11-04T05:18:49.190",
  "vulnStatus": "Awaiting Analysis",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "The Goodix GT9xx input driver in drivers/input/input_gt911.c reads the touch point count from the controller's status register and masks it with GT911_TOUCH_POINTS_MSK (0x0F), yielding a value of 0..15. In gt911_process() that value is used directly as the loop bound for filling point_reg[], a stack array sized to CONFIG_INPUT_GT911_MAX_TOUCH_POINTS, whose Kconfig range is 1..5 with a default of 1. No other check constrains the count; the driver relied only on a comment asserting that the controller had been programmed at init to report no more points than configured.\n\nEach loop iteration issues an I2C read of eight bytes straight into point_reg[i], so a controller that reports more points than the array holds causes up to 112 bytes of peer-supplied data to be written past the end of the array, over the stack frame of gt911_process() in the system workqueue thread. Two further loops then read out of bounds from the same array. Triggering it requires control of, or the ability to substitute, the I2C touch controller — plausible on the many supported boards where the GT9xx panel is a pluggable display module or shield rather than an on-PCB part; a spoofed device need only answer the init probes with a supported product ID and a checksum-valid config blob. The same overflow can also occur non-adversarially, with a GT9271-class panel that ignores the driver's touch-count programming and reports up to ten points, or with bus corruption of the single status byte.\n\nThe impact is an out-of-bounds stack write with fully attacker-chosen content executing at kernel privilege, i.e. potential control-flow hijack on the host MCU, in addition to out-of-bounds reads and crashes. The attack vector is physical/local hardware access only; there is no network, USB, or syscall path to the defect. The fix clamps the reported count with min() against CONFIG_INPUT_GT911_MAX_TOUCH_POINTS before any array indexing."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "zephyrproject",
          "product": "zephyr",
          "defaultStatus": "unaffected",
          "collectionURL": "https://github.com/zephyrproject-rtos/zephyr",
          "packageName": "zephyr",
          "programFiles": [
            "drivers/input/input_gt911.c"
          ],
          "programRoutines": [
            {
              "name": "gt911_process"
            }
          ],
          "versions": [
            {
              "version": "4.0.0",
              "lessThan": "4.5.0",
              "versionType": "semver",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "[email protected]",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
          "baseScore": 6.8,
          "baseSeverity": "MEDIUM",
          "attackVector": "PHYSICAL",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 0.9,
        "impactScore": 5.9
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-10-15T17:57:40.802963Z",
          "id": "CVE-2026-19576",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-787"
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://github.com/zephyrproject-rtos/zephyr/commit/42b52d571eb2113012c135276693042fd372fdea",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-p7qh-fvwx-f7vr",
      "source": "[email protected]"
    }
  ]
}