Vulnerability-Lookup

FKIE_CVE-2026-43423

Vulnerability from fkie_nvd - Published: 2026-05-08 15:16 - Updated: 2026-05-12 14:10

Severity

Summary

In the Linux kernel, the following vulnerability has been resolved: usb: gadget: f_ncm: Fix atomic context locking issue The ncm_set_alt function was holding a mutex to protect against races with configfs, which invokes the might-sleep function inside an atomic context. Remove the struct net_device pointer from the f_ncm_opts structure to eliminate the contention. The connection state is now managed by a new boolean flag to preserve the use-after-free fix from commit 6334b8e4553c ("usb: gadget: f_ncm: Fix UAF ncm object at re-bind after usb ep transport error"). BUG: sleeping function called from invalid context Call Trace: dump_stack_lvl+0x83/0xc0 dump_stack+0x14/0x16 __might_resched+0x389/0x4c0 __might_sleep+0x8e/0x100 ... __mutex_lock+0x6f/0x1740 ... ncm_set_alt+0x209/0xa40 set_config+0x6b6/0xb40 composite_setup+0x734/0x2b40 ...

References

	URL	Tags
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/0d6c8144ca4d93253de952a5ea0028c19ed7ab68
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/e533a44fb1b337d14f772585b67328bee2e0b5e3
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/e95120b4b95ef1c16d8e94e201ae89f5e59e2612

Impacted products

	Vendor	Product	Version

JSON

To clipboard

{
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nusb: gadget: f_ncm: Fix atomic context locking issue\n\nThe ncm_set_alt function was holding a mutex to protect against races\nwith configfs, which invokes the might-sleep function inside an atomic\ncontext.\n\nRemove the struct net_device pointer from the f_ncm_opts structure to\neliminate the contention. The connection state is now managed by a new\nboolean flag to preserve the use-after-free fix from\ncommit 6334b8e4553c (\"usb: gadget: f_ncm: Fix UAF ncm object at re-bind\nafter usb ep transport error\").\n\nBUG: sleeping function called from invalid context\nCall Trace:\n dump_stack_lvl+0x83/0xc0\n dump_stack+0x14/0x16\n __might_resched+0x389/0x4c0\n __might_sleep+0x8e/0x100\n ...\n __mutex_lock+0x6f/0x1740\n ...\n ncm_set_alt+0x209/0xa40\n set_config+0x6b6/0xb40\n composite_setup+0x734/0x2b40\n ..."
    }
  ],
  "id": "CVE-2026-43423",
  "lastModified": "2026-05-12T14:10:27.343",
  "metrics": {},
  "published": "2026-05-08T15:16:54.390",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/0d6c8144ca4d93253de952a5ea0028c19ed7ab68"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/e533a44fb1b337d14f772585b67328bee2e0b5e3"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/e95120b4b95ef1c16d8e94e201ae89f5e59e2612"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Undergoing Analysis"
}

CVE-2026-43423 (GCVE-0-2026-43423)

Vulnerability from cvelistv5 – Published: 2026-05-08 14:21 – Updated: 2026-05-11 22:24

Title

usb: gadget: f_ncm: Fix atomic context locking issue

Summary

Severity

No CVSS data available.

Assigner

Linux

References

3 references

URL	Tags
https://git.kernel.org/stable/c/e533a44fb1b337d14…
https://git.kernel.org/stable/c/e95120b4b95ef1c16…
https://git.kernel.org/stable/c/0d6c8144ca4d93253…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: b62076e780a2121903ecf9ffdfb89c64647cb7da , < e533a44fb1b337d14f772585b67328bee2e0b5e3 (git) Affected: 188338c1827842f898761a939669cf345bdf07e2 , < e95120b4b95ef1c16d8e94e201ae89f5e59e2612 (git) Affected: 56a512a9b4107079f68701e7d55da8507eb963d9 , < 0d6c8144ca4d93253de952a5ea0028c19ed7ab68 (git)
Linux	Linux	Affected: 6.18.17 , < 6.18.19 (semver) Affected: 6.19.7 , < 6.19.9 (semver)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/usb/gadget/function/f_ncm.c",
            "drivers/usb/gadget/function/u_ether_configfs.h",
            "drivers/usb/gadget/function/u_ncm.h"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "e533a44fb1b337d14f772585b67328bee2e0b5e3",
              "status": "affected",
              "version": "b62076e780a2121903ecf9ffdfb89c64647cb7da",
              "versionType": "git"
            },
            {
              "lessThan": "e95120b4b95ef1c16d8e94e201ae89f5e59e2612",
              "status": "affected",
              "version": "188338c1827842f898761a939669cf345bdf07e2",
              "versionType": "git"
            },
            {
              "lessThan": "0d6c8144ca4d93253de952a5ea0028c19ed7ab68",
              "status": "affected",
              "version": "56a512a9b4107079f68701e7d55da8507eb963d9",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/usb/gadget/function/f_ncm.c",
            "drivers/usb/gadget/function/u_ether_configfs.h",
            "drivers/usb/gadget/function/u_ncm.h"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "6.18.19",
              "status": "affected",
              "version": "6.18.17",
              "versionType": "semver"
            },
            {
              "lessThan": "6.19.9",
              "status": "affected",
              "version": "6.19.7",
              "versionType": "semver"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.19",
                  "versionStartIncluding": "6.18.17",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.19.9",
                  "versionStartIncluding": "6.19.7",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nusb: gadget: f_ncm: Fix atomic context locking issue\n\nThe ncm_set_alt function was holding a mutex to protect against races\nwith configfs, which invokes the might-sleep function inside an atomic\ncontext.\n\nRemove the struct net_device pointer from the f_ncm_opts structure to\neliminate the contention. The connection state is now managed by a new\nboolean flag to preserve the use-after-free fix from\ncommit 6334b8e4553c (\"usb: gadget: f_ncm: Fix UAF ncm object at re-bind\nafter usb ep transport error\").\n\nBUG: sleeping function called from invalid context\nCall Trace:\n dump_stack_lvl+0x83/0xc0\n dump_stack+0x14/0x16\n __might_resched+0x389/0x4c0\n __might_sleep+0x8e/0x100\n ...\n __mutex_lock+0x6f/0x1740\n ...\n ncm_set_alt+0x209/0xa40\n set_config+0x6b6/0xb40\n composite_setup+0x734/0x2b40\n ..."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-05-11T22:24:18.117Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/e533a44fb1b337d14f772585b67328bee2e0b5e3"
        },
        {
          "url": "https://git.kernel.org/stable/c/e95120b4b95ef1c16d8e94e201ae89f5e59e2612"
        },
        {
          "url": "https://git.kernel.org/stable/c/0d6c8144ca4d93253de952a5ea0028c19ed7ab68"
        }
      ],
      "title": "usb: gadget: f_ncm: Fix atomic context locking issue",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-43423",
    "datePublished": "2026-05-08T14:21:57.683Z",
    "dateReserved": "2026-05-01T14:12:56.008Z",
    "dateUpdated": "2026-05-11T22:24:18.117Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

Action not permitted

FKIE_CVE-2026-43423

CVE-2026-43423 (GCVE-0-2026-43423)

Tags

Sightings

Nomenclature