{"api_version":"1","generated_at":"2026-08-01T20:43:26+00:00","cve":"CVE-2026-64302","urls":{"html":"https://cve.report/CVE-2026-64302","api":"https://cve.report/api/cve/CVE-2026-64302.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-64302","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-64302"},"summary":{"title":"x86/mm: Fix freeing of PMD-sized vmemmap pages","description":"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 ]","state":"PUBLISHED","assigner":"Linux","published_at":"2026-07-25 10:17:11","updated_at":"2026-07-25 10:17:11"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/03f6ecbc446c33b38fd452cd3c494092a8116967","name":"https://git.kernel.org/stable/c/03f6ecbc446c33b38fd452cd3c494092a8116967","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/39406c05f8f150f1685839acd38ffdd69ff92031","name":"https://git.kernel.org/stable/c/39406c05f8f150f1685839acd38ffdd69ff92031","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/add1e4112e00b619614784bf630aeebfdefa23e1","name":"https://git.kernel.org/stable/c/add1e4112e00b619614784bf630aeebfdefa23e1","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-64302","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-64302","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected a1593c90896babf33e947910c7aecb9f50bab993 add1e4112e00b619614784bf630aeebfdefa23e1 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected bf9e4e30f3538391745a99bc2268ec4f5e4a401e 03f6ecbc446c33b38fd452cd3c494092a8116967 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected bf9e4e30f3538391745a99bc2268ec4f5e4a401e 39406c05f8f150f1685839acd38ffdd69ff92031 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.18.7 6.18.39 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.19","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.19 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.39 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.1.4 7.1.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2-rc1 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":{"cve_year":"2026","cve_id":"64302","cve":"CVE-2026-64302","epss":"0.001980000","percentile":"0.098930000","score_date":"2026-07-28","updated_at":"2026-07-29 00:05:33"},"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["arch/x86/mm/init_64.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"add1e4112e00b619614784bf630aeebfdefa23e1","status":"affected","version":"a1593c90896babf33e947910c7aecb9f50bab993","versionType":"git"},{"lessThan":"03f6ecbc446c33b38fd452cd3c494092a8116967","status":"affected","version":"bf9e4e30f3538391745a99bc2268ec4f5e4a401e","versionType":"git"},{"lessThan":"39406c05f8f150f1685839acd38ffdd69ff92031","status":"affected","version":"bf9e4e30f3538391745a99bc2268ec4f5e4a401e","versionType":"git"},{"lessThan":"6.18.39","status":"affected","version":"6.18.7","versionType":"semver"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["arch/x86/mm/init_64.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"6.19"},{"lessThan":"6.19","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.39","versionType":"semver"},{"lessThanOrEqual":"7.1.*","status":"unaffected","version":"7.1.4","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.2-rc1","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.39","versionStartIncluding":"6.18.7","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.1.4","versionStartIncluding":"6.19","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2-rc1","versionStartIncluding":"6.19","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"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 ]"}],"providerMetadata":{"dateUpdated":"2026-07-25T08:49:37.621Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/add1e4112e00b619614784bf630aeebfdefa23e1"},{"url":"https://git.kernel.org/stable/c/03f6ecbc446c33b38fd452cd3c494092a8116967"},{"url":"https://git.kernel.org/stable/c/39406c05f8f150f1685839acd38ffdd69ff92031"}],"title":"x86/mm: Fix freeing of PMD-sized vmemmap pages","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-64302","datePublished":"2026-07-25T08:49:37.621Z","dateReserved":"2026-07-19T15:36:31.779Z","dateUpdated":"2026-07-25T08:49:37.621Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-07-25 10:17:11","lastModifiedDate":"2026-07-25 10:17:11","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"64302","Ordinal":"1","Title":"x86/mm: Fix freeing of PMD-sized vmemmap pages","CVE":"CVE-2026-64302","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"64302","Ordinal":"1","NoteData":"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 ]","Type":"Description","Title":"x86/mm: Fix freeing of PMD-sized vmemmap pages"}]}}}