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CVE-2026-31723

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: usb: gadget: f_subset: Fix net_device lifecycle with device_move The net_device is allocated during function instance creation and registered during the bind phase with the gadget device as its sysfs parent. When the function unbinds, the parent device is destroyed, but the net_device survives, resulting in dangling sysfs symlinks: console:/ # ls -l /sys/class/net/usb0 lrwxrwxrwx ... /sys/class/net/usb0 -> /sys/devices/platform/.../gadget.0/net/usb0 console:/ # ls -l /sys/devices/platform/.../gadget.0/net/usb0 ls: .../gadget.0/net/usb0: No such file or directory Use device_move() to reparent the net_device between the gadget device tree and /sys/devices/virtual across bind and unbind cycles. During the final unbind, calling device_move(NULL) moves the net_device to the virtual device tree before the gadget device is destroyed. On rebinding, device_move() reparents the device back under the new gadget, ensuring proper sysfs topology and power management ordering. To maintain compatibility with legacy composite drivers (e.g., multi.c), the bound flag is used to indicate whether the network device is shared and pre-registered during the legacy driver's bind phase.

Severity
MEDIUM
CVSS score
5.5 (v3.1)
Vulnerability status
Modified
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-05-01 15:16:34.727000
Last modified
2026-10-30 13:18:43.210000
View original CVE JSON 
{
  "id": "CVE-2026-31723",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-05-01T15:16:34.727",
  "lastModified": "2026-10-30T13:18:43.210",
  "vulnStatus": "Modified",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nusb: gadget: f_subset: Fix net_device lifecycle with device_move\n\nThe net_device is allocated during function instance creation and\nregistered during the bind phase with the gadget device as its sysfs\nparent. When the function unbinds, the parent device is destroyed, but\nthe net_device survives, resulting in dangling sysfs symlinks:\n\n  console:/ # ls -l /sys/class/net/usb0\n  lrwxrwxrwx ... /sys/class/net/usb0 ->\n  /sys/devices/platform/.../gadget.0/net/usb0\n  console:/ # ls -l /sys/devices/platform/.../gadget.0/net/usb0\n  ls: .../gadget.0/net/usb0: No such file or directory\n\nUse device_move() to reparent the net_device between the gadget device\ntree and /sys/devices/virtual across bind and unbind cycles. During the\nfinal unbind, calling device_move(NULL) moves the net_device to the\nvirtual device tree before the gadget device is destroyed. On rebinding,\ndevice_move() reparents the device back under the new gadget, ensuring\nproper sysfs topology and power management ordering.\n\nTo maintain compatibility with legacy composite drivers (e.g., multi.c),\nthe bound flag is used to indicate whether the network device is shared\nand pre-registered during the legacy driver's bind phase."
    }
  ],
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          "baseScore": 5.5,
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          "attackVector": "LOCAL",
          "attackComplexity": "LOW",
          "privilegesRequired": "LOW",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "availabilityImpact": "HIGH"
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        "exploitabilityScore": 1.8,
        "impactScore": 3.6
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  "weaknesses": [
    {
      "source": "[email protected]",
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      "description": [
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