{
  "affected": [
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:14",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "details": "In the Linux kernel, the following vulnerability has been resolved:  cxl/features: bound fwctl command payload to the input buffer  fwctl_cmd_rpc() copies cmd-\u003ein_len bytes into inbuf = kvzalloc(cmd-\u003ein_len) and passes inbuf and in_len to -\u003efw_rpc(). The CXL callback cxlctl_fw_rpc() ignores in_len and never checks the user-controlled op_size against it.  cxlctl_set_feature() bounds op_size only from below (op_size \u003c= sizeof(feat_in-\u003ehdr)) and then reads op_size - sizeof(hdr) bytes from feat_in-\u003efeat_data via cxl_set_feature(). With a small in_len and a large op_size the first memcpy() already reads past the kvzalloc(in_len) buffer; the out-of-bounds bytes are placed in the mailbox payload and sent to the device, and a large enough op_size can walk into unmapped memory and oops the kernel. The Get paths pin op_size to a fixed size but likewise read the input struct without checking in_len.  Reject, at the single dispatch point, any request whose fixed header plus op_size does not fit in the copied-in buffer. The lower-bound test guards the subtraction and ensures op_size was copied in before it is read.",
  "id": "DEBIAN-CVE-2026-89571",
  "modified": "2026-09-14T08:47:40.404371432Z",
  "published": "2026-09-11T20:19:41.160Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://security-tracker.debian.org/tracker/CVE-2026-89571"
    }
  ],
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "upstream": [
    "CVE-2026-89571"
  ]
}