CVE-2025-71089: Software Security Vulnerability Vulnerability

{
  "schema_version" : "1.4.0",
  "id" : "GHSA-r6cc-j9rp-4f85",
  "modified" : "2026-02-26T21:31:26Z",
  "published" : "2026-01-13T18:31:06Z",
  "aliases" : [ "CVE-2025-71089" ],
  "details" : "In the Linux kernel, the following vulnerability has been resolved:\n\niommu: disable SVA when CONFIG_X86 is set\n\nPatch series \"Fix stale IOTLB entries for kernel address space\", v7.\n\nThis proposes a fix for a security vulnerability related to IOMMU Shared\nVirtual Addressing (SVA).  In an SVA context, an IOMMU can cache kernel\npage table entries.  When a kernel page table page is freed and\nreallocated for another purpose, the IOMMU might still hold stale,\nincorrect entries.  This can be exploited to cause a use-after-free or\nwrite-after-free condition, potentially leading to privilege escalation or\ndata corruption.\n\nThis solution introduces a deferred freeing mechanism for kernel page\ntable pages, which provides a safe window to notify the IOMMU to\ninvalidate its caches before the page is reused.\n\n\nThis patch (of 8):\n\nIn the IOMMU Shared Virtual Addressing (SVA) context, the IOMMU hardware\nshares and walks the CPU's page tables.  The x86 architecture maps the\nkernel's virtual address space into the upper portion of every process's\npage table.  Consequently, in an SVA context, the IOMMU hardware can walk\nand cache kernel page table entries.\n\nThe Linux kernel currently lacks a notification mechanism for kernel page\ntable changes, specifically when page table pages are freed and reused. \nThe IOMMU driver is only notified of changes to user virtual address\nmappings.  This can cause the IOMMU's internal caches to retain stale\nentries for kernel VA.\n\nUse-After-Free (UAF) and Write-After-Free (WAF) conditions arise when\nkernel page table pages are freed and later reallocated.  The IOMMU could\nmisinterpret the new data as valid page table entries.  The IOMMU might\nthen walk into attacker-controlled memory, leading to arbitrary physical\nmemory DMA access or privilege escalation.  This is also a\nWrite-After-Free issue, as the IOMMU will potentially continue to write\nAccessed and Dirty bits to the freed memory while attempting to walk the\nstale page tables.\n\nCurrently, SVA contexts are unprivileged and cannot access kernel\nmappings.  However, the IOMMU will still walk kernel-only page tables all\nthe way down to the leaf entries, where it realizes the mapping is for the\nkernel and errors out.  This means the IOMMU still caches these\nintermediate page table entries, making the described vulnerability a real\nconcern.\n\nDisable SVA on x86 architecture until the IOMMU can receive notification\nto flush the paging cache before freeing the CPU kernel page table pages.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"
  } ],
  "affected" : [ ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2025-71089"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/240cd7f2812cc25496b12063d11c823618f364e9"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/72f98ef9a4be30d2a60136dd6faee376f780d06c"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/7cad37e358970af1bb49030ff01f06a69fa7d985"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/b34289505180a83607fcfdce14b5a290d0528476"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/c2c3f1a3fd74ef16cf115f0c558616a13a8471b4"
  }, {
    "type" : "WEB",
    "url" : "https://git.kernel.org/stable/c/c341dee80b5df49a936182341b36395c831c2661"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-416" ],
    "severity" : "HIGH",
    "github_reviewed" : false,
    "github_reviewed_at" : null,
    "nvd_published_at" : "2026-01-13T16:16:08Z"
  }
}