FKIE_CVE-2025-21786

Vulnerability from fkie_nvd - Published: 2025-02-27 03:15 - Updated: 2026-06-17 08:44
Severity
7.8 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: workqueue: Put the pwq after detaching the rescuer from the pool The commit 68f83057b913("workqueue: Reap workers via kthread_stop() and remove detach_completion") adds code to reap the normal workers but mistakenly does not handle the rescuer and also removes the code waiting for the rescuer in put_unbound_pool(), which caused a use-after-free bug reported by Cheung Wall. To avoid the use-after-free bug, the pool’s reference must be held until the detachment is complete. Therefore, move the code that puts the pwq after detaching the rescuer from the pool.
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/835b69c868f53f959d4986bbecd561ba6f38e492Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/e76946110137703c16423baf6ee177b751a34b7ePatch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/e7c16028a424dd35be1064a68fa318be4359310fPatch
Impacted products
Vendor Product Version
linux linux_kernel *
linux linux_kernel *
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "kernel/workqueue.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "e7c16028a424dd35be1064a68fa318be4359310f",
              "status": "affected",
              "version": "68f83057b913467a999e1bf9e0da6a119668f769",
              "versionType": "git"
            },
            {
              "lessThan": "835b69c868f53f959d4986bbecd561ba6f38e492",
              "status": "affected",
              "version": "68f83057b913467a999e1bf9e0da6a119668f769",
              "versionType": "git"
            },
            {
              "lessThan": "e76946110137703c16423baf6ee177b751a34b7e",
              "status": "affected",
              "version": "68f83057b913467a999e1bf9e0da6a119668f769",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "kernel/workqueue.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.11"
            },
            {
              "lessThan": "6.11",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.16",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.13.*",
              "status": "unaffected",
              "version": "6.13.4",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.14",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "78A007D8-96E2-42F8-AAA7-55F22F10F891",
              "versionEndExcluding": "6.12.16",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "2A2093ED-74A9-43F9-AC72-50030F374EA4",
              "versionEndExcluding": "6.13.4",
              "versionStartIncluding": "6.13",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nworkqueue: Put the pwq after detaching the rescuer from the pool\n\nThe commit 68f83057b913(\"workqueue: Reap workers via kthread_stop() and\nremove detach_completion\") adds code to reap the normal workers but\nmistakenly does not handle the rescuer and also removes the code waiting\nfor the rescuer in put_unbound_pool(), which caused a use-after-free bug\nreported by Cheung Wall.\n\nTo avoid the use-after-free bug, the pool\u2019s reference must be held until\nthe detachment is complete. Therefore, move the code that puts the pwq\nafter detaching the rescuer from the pool."
    },
    {
      "lang": "es",
      "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: workqueue: colocar el pwq despu\u00e9s de separar el rescatador del grupo el commit 68f83057b913(\"workqueue: Reap workers via kthread_stop() and remove detach_completion\") agrega c\u00f3digo para recolectar los trabajadores normales, pero por error no gestiona el rescatador y tambi\u00e9n elimina el c\u00f3digo que espera al rescatador en put_unbound_pool(), lo que caus\u00f3 un error de use after free informado por Cheung Wall. Para evitar el error de use after free, la referencia del grupo debe mantenerse hasta que se complete la separaci\u00f3n. Por lo tanto, mueva el c\u00f3digo que coloca el pwq despu\u00e9s de separar el rescatador del grupo."
    }
  ],
  "id": "CVE-2025-21786",
  "lastModified": "2026-06-17T08:44:16.453",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "LOCAL",
          "availabilityImpact": "HIGH",
          "baseScore": 7.8,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 5.9,
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2025-21786",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2025-02-27T18:14:15.335144Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2025-02-27T03:15:19.450",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/835b69c868f53f959d4986bbecd561ba6f38e492"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/e76946110137703c16423baf6ee177b751a34b7e"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/e7c16028a424dd35be1064a68fa318be4359310f"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-416"
        }
      ],
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "type": "Secondary"
    }
  ]
}



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