{"api_version":"1","generated_at":"2026-09-26T13:05:45+00:00","cve":"CVE-2026-98135","urls":{"html":"https://cve.report/CVE-2026-98135","api":"https://cve.report/api/cve/CVE-2026-98135.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-98135","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-98135"},"summary":{"title":"ntfs: reject invalid sectors_per_cluster in the boot sector","description":"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->cluster_size = vol->sector_size << 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.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-09-25 11:17:44","updated_at":"2026-09-25 11:17:44"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/7524c3145a3bac92bebbc47a29c007f1d874c9b3","name":"https://git.kernel.org/stable/c/7524c3145a3bac92bebbc47a29c007f1d874c9b3","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/323751a604e7533fa473874d999371592a614207","name":"https://git.kernel.org/stable/c/323751a604e7533fa473874d999371592a614207","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-98135","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98135","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6251f0b0de7d645e3591931ca4c11d8322c1866f 7524c3145a3bac92bebbc47a29c007f1d874c9b3 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6251f0b0de7d645e3591931ca4c11d8322c1866f 323751a604e7533fa473874d999371592a614207 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 7.1","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.1 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2.7 7.2.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.3-rc2 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["fs/ntfs/super.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"7524c3145a3bac92bebbc47a29c007f1d874c9b3","status":"affected","version":"6251f0b0de7d645e3591931ca4c11d8322c1866f","versionType":"git"},{"lessThan":"323751a604e7533fa473874d999371592a614207","status":"affected","version":"6251f0b0de7d645e3591931ca4c11d8322c1866f","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["fs/ntfs/super.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"7.1"},{"lessThan":"7.1","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"7.2.*","status":"unaffected","version":"7.2.7","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.3-rc2","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2.7","versionStartIncluding":"7.1","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.3-rc2","versionStartIncluding":"7.1","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"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->cluster_size = vol->sector_size << 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."}],"providerMetadata":{"dateUpdated":"2026-09-25T10:36:13.510Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/7524c3145a3bac92bebbc47a29c007f1d874c9b3"},{"url":"https://git.kernel.org/stable/c/323751a604e7533fa473874d999371592a614207"}],"title":"ntfs: reject invalid sectors_per_cluster in the boot sector","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-98135","datePublished":"2026-09-25T10:36:13.510Z","dateReserved":"2026-09-25T10:25:14.319Z","dateUpdated":"2026-09-25T10:36:13.510Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-09-25 11:17:44","lastModifiedDate":"2026-09-25 11:17:44","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"98135","Ordinal":"1","Title":"ntfs: reject invalid sectors_per_cluster in the boot sector","CVE":"CVE-2026-98135","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"98135","Ordinal":"1","NoteData":"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->cluster_size = vol->sector_size << 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.","Type":"Description","Title":"ntfs: reject invalid sectors_per_cluster in the boot sector"}]}}}