{
  "cveId": "CVE-2026-64181",
  "url": "https://patchblox.com/security/cve/CVE-2026-64181",
  "summary": "CVE-2026-64181 is fixed in 20 products on 1 platform, first by ALAS2023-2026-1881, released June 22, 2026. It is not reported as exploited. Patch Radar priority: High.",
  "title": "linux: In the Linux kernel, the following vulnerability has been resolved:  mm: fix __vm_normal_page() to handle missing sup...",
  "description": "In the Linux kernel, the following vulnerability has been resolved:  mm: fix __vm_normal_page() to handle missing support for pmd_special()/pud_special()  On x86 32-bit with THP enabled, zap_huge_pmd() is seen to generate a \u0022WARNING: mm/memory.c:735 at __vm_normal_page\u002B0x6a/0x7d\u0022, from the VM_WARN_ON_ONCE(is_zero_pfn(pfn) || is_huge_zero_pfn(pfn)); followed by \u0022BUG: Bad rss-counter state\u0022s, then later \u0022BUG: Bad page state\u0022s when reclaim gets to call shrink_huge_zero_folio_scan().  It\u0027s as if the _PAGE_SPECIAL bit never got set in the huge_zero pmd: and indeed, whereas pte_special() and pte_mkspecial() are subject to a dedicated CONFIG_ARCH_HAS_PTE_SPECIAL, pmd_special() and pmd_mkspecial() are subject to CONFIG_ARCH_SUPPORTS_PMD_PFNMAP, which is never enabled on any 32-bit architecture.  While the problem was exposed through commit d80a9cb1a64a (\u0022mm/huge_memory: add and use normal_or_softleaf_folio_pmd()\u0022), it was an oversight in commit af38538801c6 (\u0022mm/memory: factor out common code from vm_normal_page_*()\u0022) and would result in other problems: * huge zero folio accounted in smaps, pagemap (PAGE_IS_FILE) and   numamaps as file-backed THP * folio_walk_start() returning the folio even without FW_ZEROPAGE set.   Callers seem to tolerate that, though.  ... and triggering the VM_WARN_ON_ONE(), although never reported so far.  To fix it, teach vm_normal_page_pmd()/vm_normal_page_pud() to consider whether pmd_special/pud_special is actually implemented.",
  "published": "2026-06-22T09:00:00Z",
  "severity": "high",
  "cvss": 7.8,
  "cvssVector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
  "epss": 0.00173,
  "epssPercentile": 0.06813,
  "priority": "High",
  "priorityTier": 3,
  "exploited": false,
  "vendorExploited": false,
  "disclosed": false,
  "fixes": [
    {
      "platform": "linux",
      "product": "bpftool6.18",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.35-68.127.amzn2023",
      "fix": "ALAS2023-2026-1881",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-1881",
      "released": "2026-06-22T09:00:00Z"
    },
    {
      "platform": "linux",
      "product": "bpftool6.18-debuginfo",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.35-68.127.amzn2023",
      "fix": "ALAS2023-2026-1881",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-1881",
      "released": "2026-06-22T09:00:00Z"
    },
    {
      "platform": "linux",
      "product": "kernel-livepatch-6.18.35-68.127",
      "release": "amzn 2023",
      "fixedVersion": "1:1.0-0.amzn2023",
      "fix": "ALAS2023-2026-1881",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-1881",
      "released": "2026-06-22T09:00:00Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.35-68.127.amzn2023",
      "fix": "ALAS2023-2026-1881",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-1881",
      "released": "2026-06-22T09:00:00Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18-debuginfo",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.35-68.127.amzn2023",
      "fix": "ALAS2023-2026-1881",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-1881",
      "released": "2026-06-22T09:00:00Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18-debuginfo-common-aarch64",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.35-68.127.amzn2023",
      "fix": "ALAS2023-2026-1881",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-1881",
      "released": "2026-06-22T09:00:00Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18-debuginfo-common-x86_64",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.35-68.127.amzn2023",
      "fix": "ALAS2023-2026-1881",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-1881",
      "released": "2026-06-22T09:00:00Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18-devel",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.35-68.127.amzn2023",
      "fix": "ALAS2023-2026-1881",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-1881",
      "released": "2026-06-22T09:00:00Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18-headers",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.35-68.127.amzn2023",
      "fix": "ALAS2023-2026-1881",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-1881",
      "released": "2026-06-22T09:00:00Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18-modules-extra",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.35-68.127.amzn2023",
      "fix": "ALAS2023-2026-1881",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-1881",
      "released": "2026-06-22T09:00:00Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18-modules-extra-common",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.35-68.127.amzn2023",
      "fix": "ALAS2023-2026-1881",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-1881",
      "released": "2026-06-22T09:00:00Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18-tools",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.35-68.127.amzn2023",
      "fix": "ALAS2023-2026-1881",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-1881",
      "released": "2026-06-22T09:00:00Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18-tools-debuginfo",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.35-68.127.amzn2023",
      "fix": "ALAS2023-2026-1881",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-1881",
      "released": "2026-06-22T09:00:00Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18-tools-devel",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.35-68.127.amzn2023",
      "fix": "ALAS2023-2026-1881",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-1881",
      "released": "2026-06-22T09:00:00Z"
    },
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 14",
      "fixedVersion": "7.0.12-1",
      "fix": "DEBIAN-CVE-2026-64181",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-64181",
      "released": "2026-07-20T12:58:36Z"
    },
    {
      "platform": "linux",
      "product": "microvm-kernel6.18",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.35-68.127.amzn2023",
      "fix": "ALAS2023-2026-1881",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-1881",
      "released": "2026-06-22T09:00:00Z"
    },
    {
      "platform": "linux",
      "product": "perf6.18",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.35-68.127.amzn2023",
      "fix": "ALAS2023-2026-1881",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-1881",
      "released": "2026-06-22T09:00:00Z"
    },
    {
      "platform": "linux",
      "product": "perf6.18-debuginfo",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.35-68.127.amzn2023",
      "fix": "ALAS2023-2026-1881",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-1881",
      "released": "2026-06-22T09:00:00Z"
    },
    {
      "platform": "linux",
      "product": "python3-perf6.18",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.35-68.127.amzn2023",
      "fix": "ALAS2023-2026-1881",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-1881",
      "released": "2026-06-22T09:00:00Z"
    },
    {
      "platform": "linux",
      "product": "python3-perf6.18-debuginfo",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.35-68.127.amzn2023",
      "fix": "ALAS2023-2026-1881",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-1881",
      "released": "2026-06-22T09:00:00Z"
    }
  ],
  "noFixYet": [],
  "dataAsOf": "2026-11-08T06:59:42Z",
  "attribution": {
    "text": "Data: Patchblox Patch Radar",
    "url": "https://patchblox.com/security/patch-radar",
    "terms": "https://patchblox.com/security/patch-radar/use-the-data"
  }
}