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CVE-2026-89668

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: nfsd: move nfsd_debugfs_init() after nfsd4_init_slabs() in init_nfsd() nfsd_debugfs_init() runs before nfsd4_init_slabs() in init_nfsd(). If the slab allocation fails, the bare "return retval" bypasses nfsd_debugfs_exit(), leaving orphan debugfs files with stale fops pointers into the freed module text. Move nfsd_debugfs_init() to after the slab init succeeds, so the early return has no debugfs state to clean up. Since debugfs is now the more recently initialized of the two, also update the unwind paths to match reverse-initialization (LIFO) order: run nfsd_debugfs_exit() before nfsd4_free_slabs() in both the init_nfsd() error path and exit_nfsd(). The nfsd debugfs files only reference module-global state and have no dependency on the slab caches, so that reordering is a cleanup with no functional change.

Severity
HIGH
CVSS score
7.8 (v3.1)
Vulnerability status
Received
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-09-11 20:19:53.290000
Last modified
2026-10-19 09:18:04.880000
View original CVE JSON
{
  "id": "CVE-2026-89668",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-09-11T20:19:53.290",
  "lastModified": "2026-10-19T09:18:04.880",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnfsd: move nfsd_debugfs_init() after nfsd4_init_slabs() in init_nfsd()\n\nnfsd_debugfs_init() runs before nfsd4_init_slabs() in init_nfsd().\nIf the slab allocation fails, the bare \"return retval\" bypasses\nnfsd_debugfs_exit(), leaving orphan debugfs files with stale fops\npointers into the freed module text.\n\nMove nfsd_debugfs_init() to after the slab init succeeds, so the\nearly return has no debugfs state to clean up.\n\nSince debugfs is now the more recently initialized of the two, also\nupdate the unwind paths to match reverse-initialization (LIFO) order:\nrun nfsd_debugfs_exit() before nfsd4_free_slabs() in both the\ninit_nfsd() error path and exit_nfsd(). The nfsd debugfs files only\nreference module-global state and have no dependency on the slab\ncaches, so that reordering is a cleanup with no functional change."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "fs/nfsd/nfsctl.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "9fe5ea760e64f04412dbed51645a0dac7220d40a",
              "lessThan": "4ae5d7490ae6a7b83b3d607f88c499f4f85e753a",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "9fe5ea760e64f04412dbed51645a0dac7220d40a",
              "lessThan": "ab43ff94f5dfc2b6a080b167b69855eb7655c98b",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "9fe5ea760e64f04412dbed51645a0dac7220d40a",
              "lessThan": "2c390c8a1764d67095fe444401861fac4c049362",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "fs/nfsd/nfsctl.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "6.16",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "6.16",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.50",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2.4",
              "lessThanOrEqual": "7.2.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.3",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
          "baseScore": 7.8,
          "baseSeverity": "HIGH",
          "attackVector": "LOCAL",
          "attackComplexity": "LOW",
          "privilegesRequired": "LOW",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 5.9
      }
    ]
  },
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/2c390c8a1764d67095fe444401861fac4c049362",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/4ae5d7490ae6a7b83b3d607f88c499f4f85e753a",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/ab43ff94f5dfc2b6a080b167b69855eb7655c98b",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}