{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "1c3506ea8599a3ad1b9aae5cbd573134f8d18db7"
            },
            {
              "fixed": "345a6e869b33687e9268044bcaeeefd7c61da675"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "ceac7fb89e8da465aec3ac3c20477f912f5c3a6c"
            },
            {
              "fixed": "441ea32cf2755a0dc593557056b00b7caa0651f5"
            },
            {
              "fixed": "20f548cdac94860a164e5ebba4f7e4a01051cb06"
            },
            {
              "fixed": "08f0e65e784c4b20e6e620dd4f68d8636073a3d2"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "6.12.75"
            },
            {
              "fixed": "6.12.97"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "6.12.97"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.39"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.16.0"
            },
            {
              "fixed": "7.1.4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64307.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\ncrypto: ccp - Do not initialize SNP for ioctl(SNP_CONFIG)\n\nSashiko notes:\n\n\u003e if SEV initialization fails and KVM is actively running normal VMs, could a\n\u003e userspace process trigger this code path via /dev/sev ioctls (e.g.,\n\u003e SEV_PDH_GEN) and zero out MSR_VM_HSAVE_PA globally? Would the next VMRUN\n\u003e execution for an active VM trigger a general protection fault and crash the\n\u003e host?\n\nRefuse to re-try initialization if SNP is not already initialized for\nSNP_CONFIG.\n\nThis is technically an ABI break: before if SNP initialization failed it\ncould be transparently retriggered by this ioctl, and if no VMs were\nrunning, everything worked fine. Hopefully this is enough of a corner case\nthat nobody will notice, but someone does, there are a few options:\n\n* do something like symbol_get() for kvm and refuse to initialize if KVM is\n  loaded\n* check each cpu's HSAVE_PA for non-zero data before re-initializing\n* once initialization has failed, continue to refuse to initialize until\n  the ccp module is unloaded",
  "id": "CVE-2026-64307",
  "modified": "2026-07-27T03:56:28.447284780Z",
  "published": "2026-07-25T08:49:40.782Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/08f0e65e784c4b20e6e620dd4f68d8636073a3d2"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/20f548cdac94860a164e5ebba4f7e4a01051cb06"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/345a6e869b33687e9268044bcaeeefd7c61da675"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/441ea32cf2755a0dc593557056b00b7caa0651f5"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64307.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-64307"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.8.0",
  "summary": "crypto: ccp - Do not initialize SNP for ioctl(SNP_CONFIG)"
}