sysctl and platform-op locks open to abuse

{
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "cveMetadata": {
    "cveId": "CVE-2026-62427",
    "assignerOrgId": "23aa2041-22e1-471f-9209-9b7396fa234f",
    "assignerShortName": "XEN",
    "dateUpdated": "2026-07-28T12:31:57.645Z",
    "dateReserved": "2026-07-14T10:28:12.655Z",
    "datePublished": "2026-07-28T12:31:57.645Z",
    "state": "PUBLISHED"
  },
  "containers": {
    "cna": {
      "providerMetadata": {
        "orgId": "23aa2041-22e1-471f-9209-9b7396fa234f",
        "shortName": "XEN",
        "dateUpdated": "2026-07-28T12:31:57.645Z"
      },
      "datePublic": "2026-07-28T12:00:00.000Z",
      "title": "sysctl and platform-op locks open to abuse",
      "descriptions": [
        {
          "lang": "en",
          "value": "[This CNA information record relates to multiple CVEs; the\ntext explains which aspects/vulnerabilities correspond to which CVE.]\n\nTo manage the system, sysctl and platform operations are used by the\ncontrol domain or a possible Xenstore domain.  Some of these operations\nmay not be executed in parallel, so a system-wide lock each is used.\nThe way those locks are acquired is, however, not providing any fairness.\nFurthermore, with XSM/Flask in use, the lock acquire will, for some\noperations, occur ahead of any permission checking.\n\nThe sysctl issue is CVE-2026-62426.\n\nThe platform-op issue is CVE-2026-62427."
        }
      ],
      "affected": [
        {
          "vendor": "Xen",
          "product": "Xen",
          "defaultStatus": "unknown",
          "versions": [
            {
              "version": "consult Xen advisory XSA-499",
              "status": "unknown"
            }
          ]
        }
      ],
      "references": [
        {
          "url": "https://xenbits.xenproject.org/xsa/advisory-499.html"
        }
      ],
      "impacts": [
        {
          "descriptions": [
            {
              "lang": "en",
              "value": "A less privileged entity may stall an equally or more privileged entity,\npotentially leading to a Denial od Service (DoS) of up to the entire\nhost."
            }
          ]
        }
      ],
      "configurations": [
        {
          "lang": "en",
          "value": "All Xen versions from 4.0 onwards are vulnerable.  Earlier versions use\na different locking operation, but may also be vulnerable."
        }
      ],
      "workarounds": [
        {
          "lang": "en",
          "value": "There is no known mitigation."
        }
      ],
      "credits": [
        {
          "lang": "en",
          "value": "This issue was discovered by Jan Beulich of SUSE.",
          "type": "finder"
        }
      ]
    }
  }
}