{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "0db89fa243e5edc5de38c88b369e4c3755c5fb74"
            },
            {
              "fixed": "d3af83e327565a9444cebc0db714cb837e493046"
            },
            {
              "fixed": "c5a31b4e7e37c92550be9a2edf51ca853a4d251a"
            },
            {
              "fixed": "a2151624b55029dad0ca7efd17fb83a0461c8843"
            },
            {
              "fixed": "6d4ed2fd022bc862b156e53aae163b61259e1caa"
            },
            {
              "fixed": "15d2b7f38f95d28652170344f39ee492c55e567c"
            },
            {
              "fixed": "ced45be0073a8a31b30b4a7f68cd3a15734515de"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "5.17.0"
            },
            {
              "fixed": "6.1.188"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.2.0"
            },
            {
              "fixed": "6.6.157"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.7.0"
            },
            {
              "fixed": "6.12.109"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.50"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.2.4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89587.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nACPI: pfr_update: fix stack buffer overflow in query_capability()\n\nquery_capability() copies four ACPI buffer objects returned by the\nfirmware _DSM into fixed-size u8[16] fields in struct\npfru_update_cap_info using memcpy with the firmware-supplied length:\n\n  memcpy(\u0026cap_hdr-\u003ecode_type,\n         elements[CAP_CODE_TYPE_IDX].buffer.pointer,\n         elements[CAP_CODE_TYPE_IDX].buffer.length);\n\nThe same pattern repeats for drv_type, platform_id, and oem_id.\nIf the firmware returns buffer.length \u003e 16 for any of these fields,\nmemcpy writes past the destination array.\n\nstruct pfru_update_cap_info is stack-allocated in pfru_ioctl().\n\nConfirmed with KASAN on 7.2-rc6: three stack-out-of-bounds reports\nare generated when a DSM returns 64-byte buffers, with writes reaching\n44 bytes past the end of cap_hdr's [64, 156) frame window into\nadjacent stack redzones.\n\nIntroduce a helper pointer to out_obj-\u003epackage.elements and use it\nto validate each buffer length against its destination field size\nbefore copying, returning -EINVAL if the firmware supplies an\noversized buffer.",
  "id": "CVE-2026-89587",
  "modified": "2026-09-15T03:30:55.712358742Z",
  "published": "2026-09-11T19:44:52.066Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/15d2b7f38f95d28652170344f39ee492c55e567c"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/6d4ed2fd022bc862b156e53aae163b61259e1caa"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/a2151624b55029dad0ca7efd17fb83a0461c8843"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/c5a31b4e7e37c92550be9a2edf51ca853a4d251a"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/ced45be0073a8a31b30b4a7f68cd3a15734515de"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/d3af83e327565a9444cebc0db714cb837e493046"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89587.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-89587"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "ACPI: pfr_update: fix stack buffer overflow in query_capability()"
}