{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "6251f0b0de7d645e3591931ca4c11d8322c1866f"
            },
            {
              "fixed": "7524c3145a3bac92bebbc47a29c007f1d874c9b3"
            },
            {
              "fixed": "323751a604e7533fa473874d999371592a614207"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "7.1.0"
            },
            {
              "fixed": "7.2.7"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98135.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nntfs: reject invalid sectors_per_cluster in the boot sector\n\nis_boot_sector_ntfs() checks the boot sector's sectors_per_cluster field\nwith a range test that rejects 0x81..0xf3 but accepts 0 and other\nnon-power-of-two counts. A zero value reaches parse_ntfs_boot_sector():\n\n\tsectors_per_cluster_bits = ffs(sectors_per_cluster) - 1;\n\t...\n\tvol-\u003ecluster_size = vol-\u003esector_size \u003c\u003c sectors_per_cluster_bits;\n\nffs(0) is 0, so sectors_per_cluster_bits becomes (unsigned)-1 and the\nshift is undefined:\n\n  UBSAN: shift-out-of-bounds in fs/ntfs/super.c:673:39\n  shift exponent 4294967295 is too large for 32-bit type 'int'\n\nThis change rejects any non-power-of-two value, since it feeds the\naforementioned shift via ffs() - 1, which only yields the correct shift for a\npower of two.",
  "id": "CVE-2026-98135",
  "modified": "2026-09-27T03:30:21.793064096Z",
  "published": "2026-09-25T10:36:13.510Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/323751a604e7533fa473874d999371592a614207"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/7524c3145a3bac92bebbc47a29c007f1d874c9b3"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98135.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-98135"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.9.0",
  "summary": "ntfs: reject invalid sectors_per_cluster in the boot sector"
}