{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "5db1bef933427aa467ad89c7b695a84a6b4afe16"
            },
            {
              "fixed": "faf66e55e87498ab4bf88cdf9a629e61b3f2d3bc"
            },
            {
              "fixed": "bae3e4493046de4fefa15f809d9b8dc114e84a3d"
            },
            {
              "fixed": "2a2eb10795a1e495aebc7f829ccecb72c05b4fd9"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "6.16.0"
            },
            {
              "fixed": "6.18.55"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.2.9"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98638.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: arm64: Validate the SVE vector length in pkvm_vcpu_init_sve()\n\npkvm_vcpu_init_sve() clamps only the upper bound of the host-provided\nsve_max_vl, so an invalid vector length reaches sve_state_size_from_vl()\nand the WARN_ON() there, which is fatal at EL2. The existing\n!sve_state_size test rejects such a length, but only after the macro has\nrun.\n\nCheck sve_vl_valid() before deriving the state size. A valid length\ncannot yield a zero size, so the !sve_state_size test goes with it.",
  "id": "CVE-2026-98638",
  "modified": "2026-10-20T02:30:20.339558247Z",
  "published": "2026-10-18T15:20:09.380Z",
  "references": [
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/2a2eb10795a1e495aebc7f829ccecb72c05b4fd9"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/bae3e4493046de4fefa15f809d9b8dc114e84a3d"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/faf66e55e87498ab4bf88cdf9a629e61b3f2d3bc"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98638.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-98638"
    }
  ],
  "schema_version": "1.9.0",
  "summary": "KVM: arm64: Validate the SVE vector length in pkvm_vcpu_init_sve()"
}