{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "5212e11fde4d40fa627668b4f2222d20db488f71"
            },
            {
              "fixed": "eb491343d2d1784121ad9af91c25b338c28913c3"
            },
            {
              "fixed": "59d5cd1f42b4bab3609512c3cb3d3540d3d21da7"
            },
            {
              "fixed": "f6c5313aae794ecca8f762c1a3493de5c266f120"
            },
            {
              "fixed": "f9bf05c63b77d000e9c01f3e47af36973887d350"
            },
            {
              "fixed": "6f79d1a5f2611a3d36e9312be5425cd9cb397c51"
            },
            {
              "fixed": "6b1faf1f099f7060b5f1f2f0d024132581f1726e"
            },
            {
              "fixed": "9dfa11cef4750b67591307f2c62e47a23d60e4b7"
            },
            {
              "fixed": "6a1f2e5ed9267ca19187038ac635393c165213ac"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "4.2.0"
            },
            {
              "fixed": "5.10.270"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.11.0"
            },
            {
              "fixed": "5.15.221"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.16.0"
            },
            {
              "fixed": "6.1.188"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.2.0"
            },
            {
              "fixed": "6.6.157"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.7.0"
            },
            {
              "fixed": "6.12.110"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.51"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.2.5"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89965.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnvdimm/btt: reject an arena whose nfree is below the lane count\n\nThe BTT info block's nfree field, the number of reserve free blocks, is\nread from the medium without validation.  btt_freelist_init() and\nbtt_rtt_init() size the per-lane freelist[] and rtt[] arrays by nfree,\nbut the I/O path indexes them by the lane from nd_region_acquire_lane(),\nwhich is bounded by nd_region-\u003enum_lanes (ND_MAX_LANES), not by nfree.\nA crafted or foreign arena whose nfree is below the lane count makes\nfreelist[lane]/rtt[lane] run past the allocation: an out-of-bounds write.\n\nbtt.rst documents the nlanes = min(nfree, num_cpus) invariant, which the\ncode does not currently honor: num_lanes is ND_MAX_LANES regardless of\nnfree.  Reject an arena whose nfree is below num_lanes at discovery,\nbefore the per-lane arrays are allocated, enforcing that invariant.",
  "id": "CVE-2026-89965",
  "modified": "2026-09-17T03:30:57.294630098Z",
  "published": "2026-09-16T10:32:46.769Z",
  "references": [
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/59d5cd1f42b4bab3609512c3cb3d3540d3d21da7"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/6a1f2e5ed9267ca19187038ac635393c165213ac"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/6b1faf1f099f7060b5f1f2f0d024132581f1726e"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/6f79d1a5f2611a3d36e9312be5425cd9cb397c51"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/9dfa11cef4750b67591307f2c62e47a23d60e4b7"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/eb491343d2d1784121ad9af91c25b338c28913c3"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/f6c5313aae794ecca8f762c1a3493de5c266f120"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/f9bf05c63b77d000e9c01f3e47af36973887d350"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89965.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-89965"
    }
  ],
  "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": "nvdimm/btt: reject an arena whose nfree is below the lane count"
}