platform/x86: ISST: Validate logical CPU id and clos id

{
  "id": "cfd993931afdbc209c90a0542a6e13eb2e369e9f4c8c79cb3cd7291ff02fac44",
  "url": "https://osv.dev/vulnerability/CVE-2026-89438",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "platform/x86: ISST: Validate logical CPU id and clos id",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: platform/x86: ISST: Validate logical CPU id and clos id Validate max CLOS ID and logical CPU ID for core power feature. Reject any clos level or logical CPU number greater than the supported maximum. These are used to calculate MMIO offset.",
    "evidence": "osv:CVE-2026-89438",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "6.6.157",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.12.109",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.18.50",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "7.2.4",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "unknown",
    "structured": {
      "id": "CVE-2026-89438",
      "aliases": [
        "CVE-2026-89438"
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "type": "GIT",
              "events": [
                {
                  "introduced": "12a7d2cb811dd8a884dea088a2701fcb8d00136e"
                },
                {
                  "fixed": "0d601126c7afda9bb94dfecc8b2c0a16f20d76cb"
                },
                {
                  "fixed": "c9ee2770eb95ba316a56d776b2b66666b70c194b"
                },
                {
                  "fixed": "5b032e1dda486ca41d10536bd195bd8a559af1e2"
                },
                {
                  "fixed": "82d4afadb02fb4d7d7bb9230900904c10e49ec87"
                },
                {
                  "fixed": "124e2dbabe460c2a6e7440f4ad8af560131295c9"
                }
              ]
            }
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-89438.json"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.4.0"
                },
                {
                  "fixed": "6.6.157"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.7.0"
                },
                {
                  "fixed": "6.12.109"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.13.0"
                },
                {
                  "fixed": "6.18.50"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.19.0"
                },
                {
                  "fixed": "7.2.4"
                }
              ]
            }
          ],
          "package": {
            "name": "Kernel",
            "ecosystem": "Linux"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-89438.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:32.852744896Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/0d601126c7afda9bb94dfecc8b2c0a16f20d76cb",
        "https://git.kernel.org/stable/c/124e2dbabe460c2a6e7440f4ad8af560131295c9",
        "https://git.kernel.org/stable/c/5b032e1dda486ca41d10536bd195bd8a559af1e2",
        "https://git.kernel.org/stable/c/82d4afadb02fb4d7d7bb9230900904c10e49ec87",
        "https://git.kernel.org/stable/c/c9ee2770eb95ba316a56d776b2b66666b70c194b",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89438.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-89438",
        "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
      ],
      "provider_metadata": {
        "cna_assigner": "Linux",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89438.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-89438",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": null
  },
  "source_id": "core-osv",
  "document_id": 500143,
  "published_at": "2026-09-11T19:43:08.077+00:00"
}