{
  "cveId": "CVE-2023-46835",
  "url": "https://patchblox.com/security/cve/CVE-2023-46835",
  "summary": "CVE-2023-46835 is fixed in xen on 1 platform, first by DEBIAN-CVE-2023-46835, released January 5, 2024. It is not reported as exploited. Patch Radar priority: Routine.",
  "title": "xen: The current setup of the quarantine page tables assumes that the quarantine domain (dom_io) has been initialized with...",
  "description": "The current setup of the quarantine page tables assumes that the quarantine domain (dom_io) has been initialized with an address width of DEFAULT_DOMAIN_ADDRESS_WIDTH (48) and hence 4 page table levels.  However dom_io being a PV domain gets the AMD-Vi IOMMU page tables levels based on the maximum (hot pluggable) RAM address, and hence on systems with no RAM above the 512GB mark only 3 page-table levels are configured in the IOMMU.  On systems without RAM above the 512GB boundary amd_iommu_quarantine_init() will setup page tables for the scratch page with 4 levels, while the IOMMU will be configured to use 3 levels only, resulting in the last page table directory (PDE) effectively becoming a page table entry (PTE), and hence a device in quarantine mode gaining write access to the page destined to be a PDE.  Due to this page table level mismatch, the sink page the device gets read/write access to is no longer cleared between device assignment, possibly leading to data leaks.",
  "published": "2024-01-05T17:15:11Z",
  "severity": "medium",
  "cvss": 5.5,
  "cvssVector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N",
  "epss": 0.00284,
  "epssPercentile": 0.20992,
  "priority": "Routine",
  "priorityTier": 4,
  "exploited": false,
  "vendorExploited": false,
  "disclosed": false,
  "fixes": [
    {
      "platform": "linux",
      "product": "xen",
      "release": "Debian 12.15 (bookworm)",
      "fixedVersion": "4.17.2\u002B76-ge1f9cb16e2-1~deb12u1",
      "fix": "DEBIAN-CVE-2023-46835",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2023-46835",
      "released": "2024-01-05T17:15:11Z"
    },
    {
      "platform": "linux",
      "product": "xen",
      "release": "Debian 13.5 (trixie)",
      "fixedVersion": "4.17.2\u002B76-ge1f9cb16e2-1",
      "fix": "DEBIAN-CVE-2023-46835",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2023-46835",
      "released": "2024-01-05T17:15:11Z"
    },
    {
      "platform": "linux",
      "product": "xen",
      "release": "Debian 14",
      "fixedVersion": "4.17.2\u002B76-ge1f9cb16e2-1",
      "fix": "DEBIAN-CVE-2023-46835",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2023-46835",
      "released": "2024-01-05T17:15:11Z"
    }
  ],
  "noFixYet": [],
  "dataAsOf": "2026-11-08T13:06:02Z",
  "attribution": {
    "text": "Data: Patchblox Patch Radar",
    "url": "https://patchblox.com/security/patch-radar",
    "terms": "https://patchblox.com/security/patch-radar/use-the-data"
  }
}