{
  "affected": [
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:12",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:13",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "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:  ACPI: pfr_update: fix stack buffer overflow in query_capability()  query_capability() copies four ACPI buffer objects returned by the firmware _DSM into fixed-size u8[16] fields in struct pfru_update_cap_info using memcpy with the firmware-supplied length:    memcpy(\u0026cap_hdr-\u003ecode_type,          elements[CAP_CODE_TYPE_IDX].buffer.pointer,          elements[CAP_CODE_TYPE_IDX].buffer.length);  The same pattern repeats for drv_type, platform_id, and oem_id. If the firmware returns buffer.length \u003e 16 for any of these fields, memcpy writes past the destination array.  struct pfru_update_cap_info is stack-allocated in pfru_ioctl().  Confirmed with KASAN on 7.2-rc6: three stack-out-of-bounds reports are generated when a DSM returns 64-byte buffers, with writes reaching 44 bytes past the end of cap_hdr's [64, 156) frame window into adjacent stack redzones.  Introduce a helper pointer to out_obj-\u003epackage.elements and use it to validate each buffer length against its destination field size before copying, returning -EINVAL if the firmware supplies an oversized buffer.",
  "id": "DEBIAN-CVE-2026-89587",
  "modified": "2026-09-14T08:47:39.274559256Z",
  "published": "2026-09-11T20:19:43.170Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://security-tracker.debian.org/tracker/CVE-2026-89587"
    }
  ],
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "upstream": [
    "CVE-2026-89587"
  ]
}