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CVE-2026-90037

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: NFSD: Prevent client use-after-free during close_lru reaping An nfs4_openowner left on nn->close_lru after its final CLOSE keeps its last closed stateid in oo_last_closed_stid, holding only a raw pointer to its nfs4_client. The laundromat reaps timed-out entries, drops nn->client_lock, and calls nfs4_put_stid(), which dereferences the client through cl_lock. Nothing pins the client across that window, so a concurrent force_expire_client() can free it and nfs4_put_stid() reads freed memory. __destroy_client() hits the same race, walking clp->cl_openowners without cl_lock. Pin the client with cl_rpc_users before dropping client_lock, and skip clients already expiring. __destroy_client() then cleans up its own close_lru entries through release_last_closed_stateid(), so teardown no longer races the laundromat.

Severity
CRITICAL
CVSS score
9.8 (v3.1)
Vulnerability status
Received
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-09-16 11:17:16.910000
Last modified
2026-10-30 13:20:39.433000
View original CVE JSON
{
  "id": "CVE-2026-90037",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-09-16T11:17:16.910",
  "lastModified": "2026-10-30T13:20:39.433",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nNFSD: Prevent client use-after-free during close_lru reaping\n\nAn nfs4_openowner left on nn->close_lru after its final CLOSE keeps\nits last closed stateid in oo_last_closed_stid, holding only a raw\npointer to its nfs4_client. The laundromat reaps timed-out entries,\ndrops nn->client_lock, and calls nfs4_put_stid(), which dereferences\nthe client through cl_lock. Nothing pins the client across that\nwindow, so a concurrent force_expire_client() can free it and\nnfs4_put_stid() reads freed memory. __destroy_client() hits the same\nrace, walking clp->cl_openowners without cl_lock.\n\nPin the client with cl_rpc_users before dropping client_lock, and\nskip clients already expiring. __destroy_client() then cleans up its\nown close_lru entries through release_last_closed_stateid(), so\nteardown no longer races the laundromat."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "fs/nfsd/nfs4state.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "217526e7ecc9f6f243e976772e81eab7ab986a4c",
              "lessThan": "1d721729762a413015864b2a56d7fb86fb8efa9f",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "217526e7ecc9f6f243e976772e81eab7ab986a4c",
              "lessThan": "adc34b5df5c5d87043cb500b0867fc1c4ad0117e",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "217526e7ecc9f6f243e976772e81eab7ab986a4c",
              "lessThan": "0763482227822f7343557f086afc382086d56c4c",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "217526e7ecc9f6f243e976772e81eab7ab986a4c",
              "lessThan": "83dd59ac1c3455c2c7d8ddb582d980a13199b9b3",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "217526e7ecc9f6f243e976772e81eab7ab986a4c",
              "lessThan": "e57a9ed34ea8c17e831de59b8f1a6b2d80d347a1",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "217526e7ecc9f6f243e976772e81eab7ab986a4c",
              "lessThan": "2330b788d732f43668b965b3105b37ceb276dfea",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "fs/nfsd/nfs4state.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "3.17",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "3.17",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.1.191",
              "lessThanOrEqual": "6.1.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.6.160",
              "lessThanOrEqual": "6.6.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.12.111",
              "lessThanOrEqual": "6.12.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.51",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2.5",
              "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:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
          "baseScore": 9.8,
          "baseSeverity": "CRITICAL",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 5.9
      }
    ]
  },
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/0763482227822f7343557f086afc382086d56c4c",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/1d721729762a413015864b2a56d7fb86fb8efa9f",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/2330b788d732f43668b965b3105b37ceb276dfea",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/83dd59ac1c3455c2c7d8ddb582d980a13199b9b3",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/adc34b5df5c5d87043cb500b0867fc1c4ad0117e",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/e57a9ed34ea8c17e831de59b8f1a6b2d80d347a1",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}