Vulnerability-Lookup

FKIE_CVE-2026-64253

Vulnerability from fkie_nvd - Published: 2026-07-24 16:16 - Updated: 2026-08-17 05:17

Severity

5.5 (Medium) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Summary

In the Linux kernel, the following vulnerability has been resolved: kernel/fork: clear PF_BLOCK_TS in copy_process() PF_BLOCK_TS is only set in blk_time_get_ns() when current->plug is non-NULL, and blk_finish_plug() clears it via __blk_flush_plug() before NULLing the plug pointer. copy_process() breaks the invariant by inheriting PF_BLOCK_TS from the parent while resetting the child's plug to NULL. Clear PF_BLOCK_TS alongside that assignment so callers can rely on "PF_BLOCK_TS set implies current->plug != NULL" and dereference current->plug unguarded.

References

URL	Tags
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/77bba61a20f1b3d206f4f90e10a7bb3cd90b9619	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/99e6c712cc300883b8cbf03347d5359ec1a4d6dd	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/ee0801aceabdf583392477baf69a290b09448b8f	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/fd38b75c4b43295b10d69772a46d1c74dbd6fc81	Patch

Impacted products

Vendor	Product	Version
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	*

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "kernel/fork.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "ee0801aceabdf583392477baf69a290b09448b8f",
              "status": "affected",
              "version": "06b23f92af87a84d70881b2ecaa72e00f7838264",
              "versionType": "git"
            },
            {
              "lessThan": "99e6c712cc300883b8cbf03347d5359ec1a4d6dd",
              "status": "affected",
              "version": "06b23f92af87a84d70881b2ecaa72e00f7838264",
              "versionType": "git"
            },
            {
              "lessThan": "77bba61a20f1b3d206f4f90e10a7bb3cd90b9619",
              "status": "affected",
              "version": "06b23f92af87a84d70881b2ecaa72e00f7838264",
              "versionType": "git"
            },
            {
              "lessThan": "fd38b75c4b43295b10d69772a46d1c74dbd6fc81",
              "status": "affected",
              "version": "06b23f92af87a84d70881b2ecaa72e00f7838264",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "kernel/fork.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.9"
            },
            {
              "lessThan": "6.9",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.95",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.38",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.3",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
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              "matchCriteriaId": "E08F80D6-87F6-4B96-A3A9-F172D7A2E3AA",
              "versionEndExcluding": "6.12.95",
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  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nkernel/fork: clear PF_BLOCK_TS in copy_process()\n\nPF_BLOCK_TS is only set in blk_time_get_ns() when current-\u003eplug is\nnon-NULL, and blk_finish_plug() clears it via __blk_flush_plug()\nbefore NULLing the plug pointer.  copy_process() breaks the\ninvariant by inheriting PF_BLOCK_TS from the parent while resetting\nthe child\u0027s plug to NULL.\n\nClear PF_BLOCK_TS alongside that assignment so callers can rely on\n\"PF_BLOCK_TS set implies current-\u003eplug != NULL\" and dereference\ncurrent-\u003eplug unguarded."
    }
  ],
  "id": "CVE-2026-64253",
  "lastModified": "2026-08-17T05:17:23.850",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "LOCAL",
          "availabilityImpact": "HIGH",
          "baseScore": 5.5,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 3.6,
        "source": "nvd@nist.gov",
        "type": "Primary"
      }
    ]
  },
  "published": "2026-07-24T16:16:55.017",
  "references": [
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      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
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    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
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      "url": "https://git.kernel.org/stable/c/99e6c712cc300883b8cbf03347d5359ec1a4d6dd"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
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    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
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      "url": "https://git.kernel.org/stable/c/fd38b75c4b43295b10d69772a46d1c74dbd6fc81"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-476"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}

CVE-2026-64253 (GCVE-0-2026-64253)

Vulnerability from cvelistv5 – Published: 2026-07-24 15:31 – Updated: 2026-08-17 04:52

Title

kernel/fork: clear PF_BLOCK_TS in copy_process()

Summary

Severity

No CVSS data available.

Assigner

Linux mitre root

References

4 references

URL	Tags
https://git.kernel.org/stable/c/ee0801aceabdf5833…
https://git.kernel.org/stable/c/99e6c712cc300883b…
https://git.kernel.org/stable/c/77bba61a20f1b3d20…
https://git.kernel.org/stable/c/fd38b75c4b43295b1…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 06b23f92af87a84d70881b2ecaa72e00f7838264 , < ee0801aceabdf583392477baf69a290b09448b8f (git) Affected: 06b23f92af87a84d70881b2ecaa72e00f7838264 , < 99e6c712cc300883b8cbf03347d5359ec1a4d6dd (git) Affected: 06b23f92af87a84d70881b2ecaa72e00f7838264 , < 77bba61a20f1b3d206f4f90e10a7bb3cd90b9619 (git) Affected: 06b23f92af87a84d70881b2ecaa72e00f7838264 , < fd38b75c4b43295b10d69772a46d1c74dbd6fc81 (git)
Linux	Linux	Affected: 6.9 Unaffected: 0 , < 6.9 (semver) Unaffected: 6.12.95 , ≤ 6.12.* (semver) Unaffected: 6.18.38 , ≤ 6.18.* (semver) Unaffected: 7.1.3 , ≤ 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": [
            "kernel/fork.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
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              "status": "affected",
              "version": "06b23f92af87a84d70881b2ecaa72e00f7838264",
              "versionType": "git"
            },
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            },
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            }
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          "programFiles": [
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          ],
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            {
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              "version": "6.9"
            },
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              "version": "0",
              "versionType": "semver"
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              "lessThanOrEqual": "6.12.*",
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            },
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              "versionType": "semver"
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              "version": "7.1.3",
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}

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.

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FKIE_CVE-2026-64253

CVE-2026-64253 (GCVE-0-2026-64253)

Tags

Sightings

Nomenclature