{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-89614","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-09-11T19:38:34.735Z","datePublished":"2026-09-11T19:45:14.747Z","dateUpdated":"2026-09-13T06:31:52.589Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-09-13T06:31:52.589Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nntfs: bound the free-cluster bitmap scan to the volume\n\nvol->lcn_empty_bits_per_page is sized from vol->nr_clusters at mount, but\nntfs_cluster_alloc() bounds its scan of that array by the size of $Bitmap.\nThose are independent on-disk quantities and the mount-time check only\nrejects a $Bitmap that is too small, so an image whose $Bitmap covers more\nclusters than the volume has lets the scan index past the array.  A run\nwhose LCN lies in that gap takes the allocator straight there, since the\ncaller passes the file's own last LCN as its locality hint.  KASAN reports\na slab out-of-bounds read when a file on such a volume is extended.\n\nClamp the scan to what that array covers, mirroring the max_index\ncalculation the mount-time scan already uses, and reject a decoded LCN\nat or beyond nr_clusters in the mapping pairs decoder.  Conforming\nvolumes are unaffected."}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","baseScore":9.8,"baseSeverity":"CRITICAL"},"scenarios":[{"lang":"en","value":"AV:N - fs/ntfs registers ntfs_export_ops, so nfsd/ksmbd VFS writes on an exported NTFS volume reach ntfs_file_write_iter->iomap->ntfs_attr_expand->ntfs_cluster_alloc, and reads reach ntfs_mapping_pairs_decompress, without local shell access.\nAC:L - A crafted image whose $Bitmap covers more clusters than nr_clusters, plus a file run whose LCN sits in that gap, deterministically drives the allocator to index past lcn_empty_bits_per_page and the decoder to accept out-of-volume LCNs, with no race or victim-specific layout.\nPR:N - Triggering needs only permission to cause server-side parse or extend of mounted NTFS metadata (guest/anonymous SMB, a permissive NFS export, or an unprivileged local open/write on an already-mounted volume), not init-namespace root or CAP_SYS_ADMIN at trigger time.\nUI:N - After the crafted volume is mounted and optionally exported, ordinary remote or local write/truncate/fallocate, and reads that decompress mapping pairs, trigger the bug; no extra victim mount dialog, USB insertion, or confirmation is required during the attack.\nS:U - Slab out-of-bounds access to vol->lcn_empty_bits_per_page and misdirected block I/O remain in the host kernel/OS security domain and do not cross a VM, container, or IOMMU boundary to another authority.\nC:H - ntfs_cluster_alloc performs a KASAN-confirmed slab out-of-bounds read of lcn_empty_bits_per_page at an attacker-influenced page index, and decoded LCNs past nr_clusters make iomap reads disclose data beyond the NTFS volume, a kernel heap/OOB-read disclosure primitive.\nI:H - With zone_end set from the poisoned LCN, the bitmap scan calls ntfs_set_lcn_empty_bits() on out-of-range indices (heap OOB write of empty-bit counts) and iomap can write past the volume using those LCNs, a kernel memory-corruption primitive consistent with privilege escalation.\nA:H - KASAN reports a slab out-of-bounds access when a file on such a volume is extended; indexing past the kvmalloc array can oops, and the OOB write of lcn_empty_bits_per_page can panic or hang the host, so even failed exploitation denies service."}]}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/ntfs/lcnalloc.c","fs/ntfs/runlist.c"],"versions":[{"version":"11ccc9107dc460de28af90fac1f42404d9802735","lessThan":"dc15a9f5307d5372aef3b64bf3ed7802f530c471","status":"affected","versionType":"git"},{"version":"11ccc9107dc460de28af90fac1f42404d9802735","lessThan":"19cac7902a8ab748e15f98ddaafcf5f8882be21d","status":"affected","versionType":"git"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/ntfs/lcnalloc.c","fs/ntfs/runlist.c"],"versions":[{"version":"7.1","status":"affected"},{"version":"0","lessThan":"7.1","status":"unaffected","versionType":"semver"},{"version":"7.2.4","lessThanOrEqual":"7.2.*","status":"unaffected","versionType":"semver"},{"version":"7.3-rc1","lessThanOrEqual":"*","status":"unaffected","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"7.1","versionEndExcluding":"7.2.4"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"7.1","versionEndExcluding":"7.3-rc1"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/dc15a9f5307d5372aef3b64bf3ed7802f530c471"},{"url":"https://git.kernel.org/stable/c/19cac7902a8ab748e15f98ddaafcf5f8882be21d"}],"title":"ntfs: bound the free-cluster bitmap scan to the volume","x_generator":{"engine":"bippy-1.2.0"}}}}