← Back to CVE Explorer

CVE-2026-43127

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: ntfs3: fix circular locking dependency in run_unpack_ex Syzbot reported a circular locking dependency between wnd->rw_lock (sbi->used.bitmap) and ni->file.run_lock. The deadlock scenario: 1. ntfs_extend_mft() takes ni->file.run_lock then wnd->rw_lock. 2. run_unpack_ex() takes wnd->rw_lock then tries to acquire ni->file.run_lock inside ntfs_refresh_zone(). This creates an AB-BA deadlock. Fix this by using down_read_trylock() instead of down_read() when acquiring run_lock in run_unpack_ex(). If the lock is contended, skip ntfs_refresh_zone() - the MFT zone will be refreshed on the next MFT operation. This breaks the circular dependency since we never block waiting for run_lock while holding wnd->rw_lock.

Severity
MEDIUM
CVSS score
5.5 (v3.1)
Vulnerability status
Modified
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-05-06 12:16:29.727000
Last modified
2026-10-21 13:18:50.337000
View original CVE JSON
{
  "id": "CVE-2026-43127",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-05-06T12:16:29.727",
  "lastModified": "2026-10-21T13:18:50.337",
  "vulnStatus": "Modified",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nntfs3: fix circular locking dependency in run_unpack_ex\n\nSyzbot reported a circular locking dependency between wnd->rw_lock\n(sbi->used.bitmap) and ni->file.run_lock.\n\nThe deadlock scenario:\n1. ntfs_extend_mft() takes ni->file.run_lock then wnd->rw_lock.\n2. run_unpack_ex() takes wnd->rw_lock then tries to acquire\n   ni->file.run_lock inside ntfs_refresh_zone().\n\nThis creates an AB-BA deadlock.\n\nFix this by using down_read_trylock() instead of down_read() when\nacquiring run_lock in run_unpack_ex(). If the lock is contended,\nskip ntfs_refresh_zone() - the MFT zone will be refreshed on the\nnext MFT operation. This breaks the circular dependency since we\nnever block waiting for run_lock while holding wnd->rw_lock."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "fs/ntfs3/run.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "57f7979aefdcef66326bda47e07ee0d8be64bf21",
              "lessThan": "d60f09d2d16c44a797d8cb67015cde2508720506",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "db7fc56646cafe39599a4c21f1398e2bdfd5c185",
              "lessThan": "76016d15bbd90caa0ce7765fddf9bde8e943e601",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "5fc982fe7eca9d0cf7b25832450ebd4f7c8e1c36",
              "lessThan": "b014372b62237521444ee51384549bdf48b79015",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "5fc982fe7eca9d0cf7b25832450ebd4f7c8e1c36",
              "lessThan": "b8d22d9d8260b0f4f4d8e2898c98037c9982ea66",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "5fc982fe7eca9d0cf7b25832450ebd4f7c8e1c36",
              "lessThan": "08ce2fee1b869ecbfbd94e0eb2630e52203a2e03",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "6.6.66",
              "lessThan": "6.6.160",
              "versionType": "semver",
              "status": "affected"
            },
            {
              "version": "6.12.5",
              "lessThan": "6.12.114",
              "versionType": "semver",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "fs/ntfs3/run.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "6.13",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "6.13",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.6.160",
              "lessThanOrEqual": "6.6.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.12.114",
              "lessThanOrEqual": "6.12.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.16",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.19.6",
              "lessThanOrEqual": "6.19.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.0",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "[email protected]",
        "type": "Primary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
          "baseScore": 5.5,
          "baseSeverity": "MEDIUM",
          "attackVector": "LOCAL",
          "attackComplexity": "LOW",
          "privilegesRequired": "LOW",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 3.6
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Primary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-667"
        }
      ]
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "operator": "OR",
          "negate": false,
          "cpeMatch": [
            {
              "vulnerable": true,
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "versionStartIncluding": "6.6.66",
              "versionEndExcluding": "6.18.16",
              "matchCriteriaId": "C8B0BDB8-5231-48C2-9E23-019AE9ADD6EF"
            },
            {
              "vulnerable": true,
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "versionStartIncluding": "6.19",
              "versionEndExcluding": "6.19.6",
              "matchCriteriaId": "373EEEDA-FAA1-4FB4-B6ED-DB4DD99DBE67"
            }
          ]
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/08ce2fee1b869ecbfbd94e0eb2630e52203a2e03",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ]
    },
    {
      "url": "https://git.kernel.org/stable/c/76016d15bbd90caa0ce7765fddf9bde8e943e601",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/b014372b62237521444ee51384549bdf48b79015",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ]
    },
    {
      "url": "https://git.kernel.org/stable/c/b8d22d9d8260b0f4f4d8e2898c98037c9982ea66",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ]
    },
    {
      "url": "https://git.kernel.org/stable/c/d60f09d2d16c44a797d8cb67015cde2508720506",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}