FKIE_CVE-2026-64253

Vulnerability from fkie_nvd - Published: 2026-07-24 16:16 - Updated: 2026-11-08 16:10
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
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/77bba61a20f1b3d206f4f90e10a7bb3cd90b9619Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/99e6c712cc300883b8cbf03347d5359ec1a4d6ddPatch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/ee0801aceabdf583392477baf69a290b09448b8fPatch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/fd38b75c4b43295b10d69772a46d1c74dbd6fc81Patch
Impacted products
Vendor Product Version
linux linux_kernel *
linux linux_kernel *
linux linux_kernel *
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": [
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "E08F80D6-87F6-4B96-A3A9-F172D7A2E3AA",
              "versionEndExcluding": "6.12.95",
              "versionStartIncluding": "6.9",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "FA591B28-5D62-449E-BDBE-3C9391BF070A",
              "versionEndExcluding": "6.18.38",
              "versionStartIncluding": "6.13",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "9526B150-E2B3-4C6F-8AE5-1AF92B75AD9E",
              "versionEndExcluding": "7.1.3",
              "versionStartIncluding": "6.19",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "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."
    },
    {
      "lang": "es",
      "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nkernel/fork: limpiar PF_BLOCK_TS en copy_process()\n\nPF_BLOCK_TS solo se establece en blk_time_get_ns() cuando current -\u003e plug no es NULL, y blk_finish_plug() lo limpia a trav\u00e9s de __blk_flush_plug() antes de anular el puntero plug. copy_process() rompe el invariante al heredar PF_BLOCK_TS del padre mientras anula el plug del hijo.\n\nLimpiar PF_BLOCK_TS junto con esa asignaci\u00f3n para que los llamadores puedan confiar en \u2019PF_BLOCK_TS establecido implica current -\u003e plug != NULL\u2019 y desreferenciar current -\u003e plug sin protecci\u00f3n."
    }
  ],
  "id": "CVE-2026-64253",
  "lastModified": "2026-11-08T16:10:00.183",
  "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"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-64253",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-11-06T16:33:07.473767Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-07-24T16:16:55.017",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/77bba61a20f1b3d206f4f90e10a7bb3cd90b9619"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/99e6c712cc300883b8cbf03347d5359ec1a4d6dd"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/ee0801aceabdf583392477baf69a290b09448b8f"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "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"
    }
  ]
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.




Drag nodes to arrange them. Double-click a related vulnerability to open it, or a source to visit its link. The Physics button on the left tunes the layout and the simulation; the legend at the bottom left hides or shows nodes by kind and by sighting type.

Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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.
Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

JSON
How durations are calculated

Following the VTEM framework (Black Hat USA 2015), time to patch starts when the vendor or a coordinator was informed, total time to patch at discovery, and disclosure to patch at public disclosure; vendor response time runs from the report to its acknowledgement. Time to exploit and time unpatched start at the earliest discovery or report, falling back to public disclosure. Unpatched time ends at the first recorded patch, or the calculation time when no patch is recorded. Exploitation to patch shows the interval between those two events; a published proof of concept is a public exploit, not exploitation.

Each result shows its source dates. A negative interval means the end event came first; when date-only inputs leave the order open, the result says so. Date-only inputs are approximate. The earliest evidence wins: KEV report dates and sightings are labelled as such. Records describing another vulnerability are listed but never calculated from, and a PoC alone does not establish exploitation. Missing patch evidence does not prove that no patch exists. Filters below change the event list only.

Loading timeline…




    Related by attack behaviour

    Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.