{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "a1593c90896babf33e947910c7aecb9f50bab993"
            },
            {
              "fixed": "add1e4112e00b619614784bf630aeebfdefa23e1"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "bf9e4e30f3538391745a99bc2268ec4f5e4a401e"
            },
            {
              "fixed": "03f6ecbc446c33b38fd452cd3c494092a8116967"
            },
            {
              "fixed": "39406c05f8f150f1685839acd38ffdd69ff92031"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "6.18.7"
            },
            {
              "fixed": "6.18.39"
            }
          ],
          "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": "6.18.39"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "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-2026-64302.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nx86/mm: Fix freeing of PMD-sized vmemmap pages\n\nCommit bf9e4e30f353 (\"x86/mm: use pagetable_free()\"), switched from\nfreeing non-boot page tables through __free_pages() to\npagetable_free().\n\nHowever, the function is also called to free vmemmap pages.\n\nGiven that vmemmap pages are not page tables, already the page_ptdesc(page)\nis wrong. But worse, pagetable_free() calls:\n\n\t__free_pages(page, compound_order(page));\n\nSince vmemmap pages are not compound pages (see vmemmap_alloc_block())\n-- except for HVO, which doesn't apply here -- only first page of a\nPMD-sized vmemmap page is freed, leaking the other ones.\n\nFix it by properly decoupling pagetable and vmemmap freeing.\nfree_pagetable() no longer has to mess with SECTION_INFO, as only the\nvmemmap is marked like that in register_page_bootmem_memmap().\n\nThe indentation in remove_pmd_table() is messed up. Fix that while\ntouching it.\n\nBootmem info handling will soon be fixed up. For now, handle it\nsimilar to free_pagetable(), just avoiding the ifdef.\n\n[ dhansen: changelog munging. More imperative voice ]",
  "id": "CVE-2026-64302",
  "modified": "2026-07-27T03:56:36.207508202Z",
  "published": "2026-07-25T08:49:37.621Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/03f6ecbc446c33b38fd452cd3c494092a8116967"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/39406c05f8f150f1685839acd38ffdd69ff92031"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/add1e4112e00b619614784bf630aeebfdefa23e1"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64302.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-64302"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.8.0",
  "summary": "x86/mm: Fix freeing of PMD-sized vmemmap pages"
}