CVE-2026-58083

{
  "id": "CVE-2026-58083",
  "sourceIdentifier": "[email protected]",
  "published": "2026-08-19T08:17:12.470",
  "lastModified": "2026-10-27T12:10:00.343",
  "vulnStatus": "Analyzed",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "While the kernel was copying knotes during fork, a knote with a timer-based filter could fire and be enqueued on the kqueue's active list before the copy was complete.  The copy routine did not account for this and could enqueue the new knote a second time, corrupting the active list.  In addition, the copy routine did not hold the appropriate locks while reading knote state, allowing further races.\n\nAn unprivileged local user can trigger a use-after-free in the kernel, potentially leading to privilege escalation."
    },
    {
      "lang": "es",
      "value": "Mientras el kernel copiaba knotes durante el fork, un knote con un filtro basado en temporizador podría activarse y ser encolado en la lista activa del kqueue antes de que la copia estuviera completa. La rutina de copia no tuvo esto en cuenta y podría encolar el nuevo knote una segunda vez, corrompiendo la lista activa. Además, la rutina de copia no mantenía los bloqueos apropiados mientras leía el estado del knote, permitiendo más condiciones de carrera.\n\nUn usuario local sin privilegios puede desencadenar un uso después de liberación en el kernel, lo que podría llevar a una escalada de privilegios."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "FreeBSD",
          "product": "FreeBSD",
          "defaultStatus": "unknown",
          "modules": [
            "kqueue"
          ],
          "versions": [
            {
              "version": "15.1-RELEASE",
              "lessThan": "p2",
              "versionType": "release",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
          "baseScore": 8.4,
          "baseSeverity": "HIGH",
          "attackVector": "LOCAL",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 2.5,
        "impactScore": 5.9
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-08-19T00:00:00+00:00",
          "id": "CVE-2026-58083",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-416"
        }
      ]
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "operator": "OR",
          "negate": false,
          "cpeMatch": [
            {
              "vulnerable": true,
              "criteria": "cpe:2.3:o:freebsd:freebsd:15.1:-:*:*:*:*:*:*",
              "matchCriteriaId": "BD327D43-A2DC-49B5-A578-D2116E1E12F3"
            },
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  "references": [
    {
      "url": "https://security.freebsd.org/advisories/FreeBSD-SA-26:50.kqueue.asc",
      "source": "[email protected]",
      "tags": [
        "Vendor Advisory"
      ]
    }
  ]
}