FKIE_CVE-2026-89676

Vulnerability from fkie_nvd - Published: 2026-09-11 20:19 - Updated: 2026-10-30 13:20
Severity
9.8 (Critical) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: nfsd: fix stale s2s_cp_stateids IDR entry for async COPY For an async COPY, nfsd4_copy() called nfs4_init_copy_state() before dup_copy_fields(), so the s2s_cp_stateids IDR was pointed at &u->copy->cp_stateid -- memory in the per-rqstp COMPOUND buffer that is reused by the next request. dup_copy_fields() copies only the value into async_copy, so the IDR slot dangled at the transient buffer for the whole background copy. Any IDR walker then dereferences reused request memory: the laundromat reads cs_type from it and, if the bytes look like an expired NFS4_COPYNOTIFY_STID, follows into refcount_dec()/idr_remove()/kfree() on garbage; manage_cpntf_state() has the same exposure via idr_find(). Duplicate the fields first, then register the stateid on the stable async_copy. result->cb_stateid is unchanged.
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/14b978e8d05ce018d0afbeb6611833ef91713a02
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/745b2edfdd96b8738a94dee450adff4c7d026d5b
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/7aa34ea78f74e6ef60c8112635a87fc43d57f6c9
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/9b4e5e9ba5ae13808b8a6d229d87c54611ba0e7a
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/bdce362f49410b9def65d76c21f6259cd89696d8
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/d0beaee498e11880e72826026db0e9c9890fc114
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/nfsd/nfs4proc.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "745b2edfdd96b8738a94dee450adff4c7d026d5b",
              "status": "affected",
              "version": "e0639dc5805a9d4faaa2c07ad98fa853b9529dd3",
              "versionType": "git"
            },
            {
              "lessThan": "bdce362f49410b9def65d76c21f6259cd89696d8",
              "status": "affected",
              "version": "e0639dc5805a9d4faaa2c07ad98fa853b9529dd3",
              "versionType": "git"
            },
            {
              "lessThan": "7aa34ea78f74e6ef60c8112635a87fc43d57f6c9",
              "status": "affected",
              "version": "e0639dc5805a9d4faaa2c07ad98fa853b9529dd3",
              "versionType": "git"
            },
            {
              "lessThan": "9b4e5e9ba5ae13808b8a6d229d87c54611ba0e7a",
              "status": "affected",
              "version": "e0639dc5805a9d4faaa2c07ad98fa853b9529dd3",
              "versionType": "git"
            },
            {
              "lessThan": "14b978e8d05ce018d0afbeb6611833ef91713a02",
              "status": "affected",
              "version": "e0639dc5805a9d4faaa2c07ad98fa853b9529dd3",
              "versionType": "git"
            },
            {
              "lessThan": "d0beaee498e11880e72826026db0e9c9890fc114",
              "status": "affected",
              "version": "e0639dc5805a9d4faaa2c07ad98fa853b9529dd3",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "fs/nfsd/nfs4proc.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "4.20"
            },
            {
              "lessThan": "4.20",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.191",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.160",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.111",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.50",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.2.*",
              "status": "unaffected",
              "version": "7.2.4",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.3",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnfsd: fix stale s2s_cp_stateids IDR entry for async COPY\n\nFor an async COPY, nfsd4_copy() called nfs4_init_copy_state() before\ndup_copy_fields(), so the s2s_cp_stateids IDR was pointed at\n\u0026u-\u003ecopy-\u003ecp_stateid -- memory in the per-rqstp COMPOUND buffer that is\nreused by the next request. dup_copy_fields() copies only the value into\nasync_copy, so the IDR slot dangled at the transient buffer for the whole\nbackground copy. Any IDR walker then dereferences reused request memory:\nthe laundromat reads cs_type from it and, if the bytes look like an\nexpired NFS4_COPYNOTIFY_STID, follows into\nrefcount_dec()/idr_remove()/kfree() on garbage; manage_cpntf_state() has\nthe same exposure via idr_find().\n\nDuplicate the fields first, then register the stateid on the stable\nasync_copy. result-\u003ecb_stateid is unchanged."
    }
  ],
  "id": "CVE-2026-89676",
  "lastModified": "2026-10-30T13:20:25.820",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 9.8,
          "baseSeverity": "CRITICAL",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 5.9,
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-89676",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-10-16T19:25:55.766709Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-09-11T20:19:54.273",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/14b978e8d05ce018d0afbeb6611833ef91713a02"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/745b2edfdd96b8738a94dee450adff4c7d026d5b"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/7aa34ea78f74e6ef60c8112635a87fc43d57f6c9"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/9b4e5e9ba5ae13808b8a6d229d87c54611ba0e7a"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/bdce362f49410b9def65d76c21f6259cd89696d8"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/d0beaee498e11880e72826026db0e9c9890fc114"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Received"
}



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