Vulnerability-Lookup

FKIE_CVE-2026-72132

Vulnerability from fkie_nvd - Published: 2026-08-15 06:21 - Updated: 2026-08-17 06:18

Severity

Summary

In the Linux kernel, the following vulnerability has been resolved: NFS: Charge unstable writes by request size, not folio size nfs_folio_mark_unstable() and nfs_folio_clear_commit() charge and uncharge NR_WRITEBACK/WB_WRITEBACK by folio_nr_pages(folio) once per *request* added to or removed from a commit list. This is correct only when a folio has a single associated request. When pg_test splits a folio into N sub-folio requests (e.g. pNFS flexfiles striping with a stripe unit smaller than the folio size, or plain wsize-limited splitting), each of the N requests independently charges the whole folio's page count, inflating the accounting by a factor of N per folio. With large folios and small stripe units this reaches multiple orders of magnitude: a 2 MiB folio split into 512 4 KiB requests can charge up to 512x its real size, pushing global dirty+writeback accounting past the system's dirty threshold and forcing every buffered writer on the host into the hard-throttle path, including unrelated in-kernel NFS server threads sharing the box. Charge each request only for the pages it actually covers.

References

	URL	Tags
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/0ffc032294a29601b1019dba91aa1a930d90df17
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/1f646e23372f3444dc5f0bcb5404a49d26756add
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/27934d02cbeb8a957dd11c985a579e58d30c5270
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/a192b6c149c6ea10cc88869accb78165eb454456
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/a442c258320b689f13d2205eaeeddf8b0e630288

Impacted products

	Vendor	Product	Version

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/nfs/internal.h",
            "fs/nfs/pnfs_nfs.c",
            "fs/nfs/write.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "a442c258320b689f13d2205eaeeddf8b0e630288",
              "status": "affected",
              "version": "0c493b5cf16e28d761b6e77c7c32aa0e7af70813",
              "versionType": "git"
            },
            {
              "lessThan": "1f646e23372f3444dc5f0bcb5404a49d26756add",
              "status": "affected",
              "version": "0c493b5cf16e28d761b6e77c7c32aa0e7af70813",
              "versionType": "git"
            },
            {
              "lessThan": "0ffc032294a29601b1019dba91aa1a930d90df17",
              "status": "affected",
              "version": "0c493b5cf16e28d761b6e77c7c32aa0e7af70813",
              "versionType": "git"
            },
            {
              "lessThan": "a192b6c149c6ea10cc88869accb78165eb454456",
              "status": "affected",
              "version": "0c493b5cf16e28d761b6e77c7c32aa0e7af70813",
              "versionType": "git"
            },
            {
              "lessThan": "27934d02cbeb8a957dd11c985a579e58d30c5270",
              "status": "affected",
              "version": "0c493b5cf16e28d761b6e77c7c32aa0e7af70813",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "fs/nfs/internal.h",
            "fs/nfs/pnfs_nfs.c",
            "fs/nfs/write.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.3"
            },
            {
              "lessThan": "6.3",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.148",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.97",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.40",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.5",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2",
              "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\nNFS: Charge unstable writes by request size, not folio size\n\nnfs_folio_mark_unstable() and nfs_folio_clear_commit() charge and\nuncharge NR_WRITEBACK/WB_WRITEBACK by folio_nr_pages(folio) once per\n*request* added to or removed from a commit list. This is correct only\nwhen a folio has a single associated request. When pg_test splits a\nfolio into N sub-folio requests (e.g. pNFS flexfiles striping with a\nstripe unit smaller than the folio size, or plain wsize-limited\nsplitting), each of the N requests independently charges the whole\nfolio\u0027s page count, inflating the accounting by a factor of N per\nfolio. With large folios and small stripe units this reaches multiple\norders of magnitude: a 2 MiB folio split into 512 4 KiB requests can\ncharge up to 512x its real size, pushing global dirty+writeback\naccounting past the system\u0027s dirty threshold and forcing every\nbuffered writer on the host into the hard-throttle path, including\nunrelated in-kernel NFS server threads sharing the box.\n\nCharge each request only for the pages it actually covers."
    }
  ],
  "id": "CVE-2026-72132",
  "lastModified": "2026-08-17T06:18:12.897",
  "metrics": {},
  "published": "2026-08-15T06:21:30.657",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/0ffc032294a29601b1019dba91aa1a930d90df17"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/1f646e23372f3444dc5f0bcb5404a49d26756add"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/27934d02cbeb8a957dd11c985a579e58d30c5270"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/a192b6c149c6ea10cc88869accb78165eb454456"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/a442c258320b689f13d2205eaeeddf8b0e630288"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Received"
}

CVE-2026-72132 (GCVE-0-2026-72132)

Vulnerability from cvelistv5 – Published: 2026-08-15 05:53 – Updated: 2026-08-17 05:08

Title

NFS: Charge unstable writes by request size, not folio size

Summary

Severity

No CVSS data available.

Assigner

Linux mitre root

References

5 references

URL	Tags
https://git.kernel.org/stable/c/a442c258320b689f1…
https://git.kernel.org/stable/c/1f646e23372f3444d…
https://git.kernel.org/stable/c/0ffc032294a29601b…
https://git.kernel.org/stable/c/a192b6c149c6ea10c…
https://git.kernel.org/stable/c/27934d02cbeb8a957…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 0c493b5cf16e28d761b6e77c7c32aa0e7af70813 , < a442c258320b689f13d2205eaeeddf8b0e630288 (git) Affected: 0c493b5cf16e28d761b6e77c7c32aa0e7af70813 , < 1f646e23372f3444dc5f0bcb5404a49d26756add (git) Affected: 0c493b5cf16e28d761b6e77c7c32aa0e7af70813 , < 0ffc032294a29601b1019dba91aa1a930d90df17 (git) Affected: 0c493b5cf16e28d761b6e77c7c32aa0e7af70813 , < a192b6c149c6ea10cc88869accb78165eb454456 (git) Affected: 0c493b5cf16e28d761b6e77c7c32aa0e7af70813 , < 27934d02cbeb8a957dd11c985a579e58d30c5270 (git)
Linux	Linux	Affected: 6.3 Unaffected: 0 , < 6.3 (semver) Unaffected: 6.6.148 , ≤ 6.6.* (semver) Unaffected: 6.12.97 , ≤ 6.12.* (semver) Unaffected: 6.18.40 , ≤ 6.18.* (semver) Unaffected: 7.1.5 , ≤ 7.1.* (semver) Unaffected: 7.2 , ≤ * (original_commit_for_fix)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/nfs/internal.h",
            "fs/nfs/pnfs_nfs.c",
            "fs/nfs/write.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "a442c258320b689f13d2205eaeeddf8b0e630288",
              "status": "affected",
              "version": "0c493b5cf16e28d761b6e77c7c32aa0e7af70813",
              "versionType": "git"
            },
            {
              "lessThan": "1f646e23372f3444dc5f0bcb5404a49d26756add",
              "status": "affected",
              "version": "0c493b5cf16e28d761b6e77c7c32aa0e7af70813",
              "versionType": "git"
            },
            {
              "lessThan": "0ffc032294a29601b1019dba91aa1a930d90df17",
              "status": "affected",
              "version": "0c493b5cf16e28d761b6e77c7c32aa0e7af70813",
              "versionType": "git"
            },
            {
              "lessThan": "a192b6c149c6ea10cc88869accb78165eb454456",
              "status": "affected",
              "version": "0c493b5cf16e28d761b6e77c7c32aa0e7af70813",
              "versionType": "git"
            },
            {
              "lessThan": "27934d02cbeb8a957dd11c985a579e58d30c5270",
              "status": "affected",
              "version": "0c493b5cf16e28d761b6e77c7c32aa0e7af70813",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "fs/nfs/internal.h",
            "fs/nfs/pnfs_nfs.c",
            "fs/nfs/write.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.3"
            },
            {
              "lessThan": "6.3",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.148",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.97",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.40",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.5",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.6.148",
                  "versionStartIncluding": "6.3",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.97",
                  "versionStartIncluding": "6.3",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.40",
                  "versionStartIncluding": "6.3",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.1.5",
                  "versionStartIncluding": "6.3",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.2",
                  "versionStartIncluding": "6.3",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nNFS: Charge unstable writes by request size, not folio size\n\nnfs_folio_mark_unstable() and nfs_folio_clear_commit() charge and\nuncharge NR_WRITEBACK/WB_WRITEBACK by folio_nr_pages(folio) once per\n*request* added to or removed from a commit list. This is correct only\nwhen a folio has a single associated request. When pg_test splits a\nfolio into N sub-folio requests (e.g. pNFS flexfiles striping with a\nstripe unit smaller than the folio size, or plain wsize-limited\nsplitting), each of the N requests independently charges the whole\nfolio\u0027s page count, inflating the accounting by a factor of N per\nfolio. With large folios and small stripe units this reaches multiple\norders of magnitude: a 2 MiB folio split into 512 4 KiB requests can\ncharge up to 512x its real size, pushing global dirty+writeback\naccounting past the system\u0027s dirty threshold and forcing every\nbuffered writer on the host into the hard-throttle path, including\nunrelated in-kernel NFS server threads sharing the box.\n\nCharge each request only for the pages it actually covers."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-17T05:08:49.516Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/a442c258320b689f13d2205eaeeddf8b0e630288"
        },
        {
          "url": "https://git.kernel.org/stable/c/1f646e23372f3444dc5f0bcb5404a49d26756add"
        },
        {
          "url": "https://git.kernel.org/stable/c/0ffc032294a29601b1019dba91aa1a930d90df17"
        },
        {
          "url": "https://git.kernel.org/stable/c/a192b6c149c6ea10cc88869accb78165eb454456"
        },
        {
          "url": "https://git.kernel.org/stable/c/27934d02cbeb8a957dd11c985a579e58d30c5270"
        }
      ],
      "title": "NFS: Charge unstable writes by request size, not folio size",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-72132",
    "datePublished": "2026-08-15T05:53:08.096Z",
    "dateReserved": "2026-08-09T03:40:39.907Z",
    "dateUpdated": "2026-08-17T05:08:49.516Z",
    "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.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.

Action not permitted

FKIE_CVE-2026-72132

CVE-2026-72132 (GCVE-0-2026-72132)

Tags

Sightings

Nomenclature