KVM: s390/diag: fix racy access of physical cpu number in diag 9c handler

{
  "id": "c4810c7a2a321176815ee18b5a1859be22125ccdfc7b579fd9c68ab833a5cae6",
  "url": "https://osv.dev/vulnerability/CVE-2023-53205",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "KVM: s390/diag: fix racy access of physical cpu number in diag 9c handler",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: KVM: s390/diag: fix racy access of physical cpu number in diag 9c handler We do check for target CPU == -1, but this might change at the time we are going to use it. Hold the physical target CPU in a local variable to avoid out-of-bound accesses to the cpu arrays.",
    "evidence": "osv:CVE-2023-53205",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "5.15.121",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.1.39",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.4.4",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "high",
    "structured": {
      "id": "CVE-2023-53205",
      "aliases": [
        "CVE-2023-53205"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:H"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "type": "GIT",
              "events": [
                {
                  "introduced": "87e28a15c42cc592009c32a8c20e5789059027c2"
                },
                {
                  "fixed": "a9ccf140a2a03a0ae82be4bdfbdd17bdaea72ff5"
                },
                {
                  "fixed": "86bfb18bad60fc468e5f112cbbd918462a8dd435"
                },
                {
                  "fixed": "dc7e0192c470a53d847c79a2796f9ac429477a26"
                },
                {
                  "fixed": "0bc380beb78aa352eadbc21d934dd9606fcee808"
                }
              ]
            }
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2023-53205.json"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "5.13.0"
                },
                {
                  "fixed": "5.15.121"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "5.16.0"
                },
                {
                  "fixed": "6.1.39"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.2.0"
                },
                {
                  "fixed": "6.4.4"
                }
              ]
            }
          ],
          "package": {
            "name": "Kernel",
            "ecosystem": "Linux"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2023-53205.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:51.713210058Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/0bc380beb78aa352eadbc21d934dd9606fcee808",
        "https://git.kernel.org/stable/c/86bfb18bad60fc468e5f112cbbd918462a8dd435",
        "https://git.kernel.org/stable/c/a9ccf140a2a03a0ae82be4bdfbdd17bdaea72ff5",
        "https://git.kernel.org/stable/c/dc7e0192c470a53d847c79a2796f9ac429477a26",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/53xxx/CVE-2023-53205.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2023-53205",
        "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/2023/53xxx/CVE-2023-53205.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2023-53205",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 520122,
  "published_at": "2025-09-15T14:21:33.56+00:00"
}