{
  "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:  nvdimm/btt: reject an arena whose nfree is below the lane count  The BTT info block's nfree field, the number of reserve free blocks, is read from the medium without validation.  btt_freelist_init() and btt_rtt_init() size the per-lane freelist[] and rtt[] arrays by nfree, but the I/O path indexes them by the lane from nd_region_acquire_lane(), which is bounded by nd_region-\u003enum_lanes (ND_MAX_LANES), not by nfree. A crafted or foreign arena whose nfree is below the lane count makes freelist[lane]/rtt[lane] run past the allocation: an out-of-bounds write.  btt.rst documents the nlanes = min(nfree, num_cpus) invariant, which the code does not currently honor: num_lanes is ND_MAX_LANES regardless of nfree.  Reject an arena whose nfree is below num_lanes at discovery, before the per-lane arrays are allocated, enforcing that invariant.",
  "id": "DEBIAN-CVE-2026-89965",
  "modified": "2026-09-17T04:47:38.762379005Z",
  "published": "2026-09-16T11:17:07.033Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://security-tracker.debian.org/tracker/CVE-2026-89965"
    }
  ],
  "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-2026-89965"
  ]
}