{
  "cveId": "CVE-2026-99155",
  "url": "https://patchblox.com/security/cve/CVE-2026-99155",
  "summary": "CVE-2026-99155 is fixed in linux on 1 platform, first by DEBIAN-CVE-2026-99155, released November 3, 2026. It is not reported as exploited. Patch Radar priority: Routine.",
  "title": "scsi: xen/scsifront: Check for a NULL shadow entry on a backend response",
  "description": "In the Linux kernel, the following vulnerability has been resolved:  scsi: xen/scsifront: Check for a NULL shadow entry on a backend response  scsifront_do_response() validates the rqid in a backend response against VSCSIIF_MAX_REQS before using it to index info-\u003Eshadow[], but then dereferences the entry to test -\u003Einflight without checking that the slot is populated.  Shadow slots are NULL before a command is submitted (the host private area is zeroed at allocation) and are reset to NULL in _scsifront_put_rqid() once a request completes, so an in-range rqid that does not correspond to an outstanding request makes the frontend dereference a NULL pointer.  A malicious or buggy backend can thus crash the guest by returning a response whose rqid is in range but not in flight -- for example a spurious response before any command has been issued, or a duplicate of one already completed.  The ring has only VSCSIIF_MAX_REQS (16) slots, so before the first command every in-range rqid selects a NULL slot.  Reject a response whose shadow slot is not populated.",
  "published": "2026-10-28T11:17:35Z",
  "severity": "Moderate",
  "cvss": 5.5,
  "epss": 0.00187,
  "epssPercentile": 0.08369,
  "priority": "Routine",
  "priorityTier": 4,
  "exploited": false,
  "vendorExploited": false,
  "disclosed": false,
  "vendorAdvisory": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-99155",
  "fixes": [
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 13.5 (trixie)",
      "fixedVersion": "6.12.115-2",
      "fix": "DEBIAN-CVE-2026-99155",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-99155",
      "released": "2026-11-03T18:58:21Z"
    },
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 14",
      "fixedVersion": "7.2.13-1",
      "fix": "DEBIAN-CVE-2026-99155",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-99155",
      "released": "2026-11-03T18:58:21Z"
    }
  ],
  "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"
  }
}