{
  "cveId": "CVE-2026-80550",
  "url": "https://patchblox.com/security/cve/CVE-2026-80550",
  "summary": "CVE-2026-80550 is fixed in 2 products on 1 platform, first by DEBIAN-CVE-2026-80550, released August 27, 2026. It is not reported as exploited. Patch Radar priority: High.",
  "title": "s390/vfio_ccw: Fix out of bounds check on CCW array",
  "description": "In the Linux kernel, the following vulnerability has been resolved:  s390/vfio_ccw: Fix out of bounds check on CCW array  The routine ccwchain_calc_length() counts the number of channel command words (CCWs) that are chained together in a single channel program, and rejects anything larger than CCWCHAIN_LEN_MAX (256) CCWs.  The loop itself is \u0022do..while (count \u003C 257)\u0022, and while the logic in is_cpa_within_range() correctly adjusts between the 0-index array of CCWs and the count of CCWs starting at 1, this means it would look at a possible 257th CCW before ending the loop and (correctly) returning an error.  Fix this by restructuring the loop to break as soon as 256 CCWs (thus indexes 0-255) are examined, without looking at memory outside the range.",
  "published": "2026-08-26T15:17:09Z",
  "severity": "Moderate",
  "cvss": 7.9,
  "cvssVector": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:L",
  "epss": 0.00137,
  "epssPercentile": 0.03124,
  "priority": "High",
  "priorityTier": 3,
  "exploited": false,
  "vendorExploited": false,
  "disclosed": false,
  "vendorAdvisory": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-80550",
  "fixes": [
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 12.15 (bookworm)",
      "fixedVersion": "6.1.187-1",
      "fix": "DEBIAN-CVE-2026-80550",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-80550",
      "released": "2026-08-27T00:27:02Z"
    },
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 13.5 (trixie)",
      "fixedVersion": "6.12.105-1",
      "fix": "DEBIAN-CVE-2026-80550",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-80550",
      "released": "2026-08-27T00:27:02Z"
    },
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 14",
      "fixedVersion": "7.1.10-1",
      "fix": "DEBIAN-CVE-2026-80550",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-80550",
      "released": "2026-08-27T00:27:02Z"
    },
    {
      "platform": "linux",
      "product": "linux-6.12",
      "release": "Debian 12.15 (bookworm)",
      "fixedVersion": "6.12.107-1~deb12u1",
      "fix": "DEBIAN-CVE-2026-80550",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-80550",
      "released": "2026-08-27T00:27:02Z"
    }
  ],
  "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"
  }
}