In the Linux kernel, the following vulnerability has been resolved:
ntfs3: bound to_move in indx_insert_into_root before hdr_insert_head
indx_insert_into_root() promotes a full resident $INDEX_ROOT into
$INDEX_ALLOCATION and copies all non-last resident root entries into
a newly allocated INDEX_BUFFER via hdr_insert_head(). The source
byte count 'to_move' is summed from the on-disk resident entry sizes
and is independent of the destination buffer size, which comes from
root->index_block_size (via indx->index_bits).
A crafted NTFS image that keeps a valid, full resident root but
shrinks root->index_block_size down to 512 after the root has been
populated makes hdr_insert_head() memcpy attacker-controlled resident
entry bytes past the end of the kmalloc(1u << indx->index_bits)
allocation returned by indx_new(). For a 512-byte destination and a
resident root whose non-last entries total 560 bytes, the memcpy
overruns by 120 bytes and a following memmove extends the highest
written offset to 136 bytes past the allocation. The overflow bytes
are a direct copy of on-disk entries (via kmemdup), so they are
fully attacker-controlled.
The write is reachable from unprivileged open(O_CREAT) on a mounted
crafted NTFS image: a single sufficiently long create in a directory
whose resident root is already full forces root promotion and
triggers the copy.
This is a controlled out-of-bounds write of 120-136 bytes past a
kmalloc(index_block_size) allocation, with attacker-controlled
content. It is a bounded adjacent-heap corruption primitive; it is
not an arbitrary-address write. Successful exploitation into a named
victim object depends on the surrounding slab layout.
Reject the copy at the sink. The destination's INDEX_HDR already
reports hdr_total (the payload capacity of the new buffer) and
hdr_used (the bytes already consumed by the terminal END entry
installed by indx_new()); require that to_move fits in the remaining
payload before calling hdr_insert_head(). On mismatch, fail with
-EINVAL and mark the filesystem as having a detected on-disk
inconsistency, which is the same behaviour as the surrounding
validation in this function.
Metrics
Affected Vendors & Products
| Vendors | Products |
|---|---|
| Linux |
|
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References
History
Sat, 15 Aug 2026 06:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | In the Linux kernel, the following vulnerability has been resolved: ntfs3: bound to_move in indx_insert_into_root before hdr_insert_head indx_insert_into_root() promotes a full resident $INDEX_ROOT into $INDEX_ALLOCATION and copies all non-last resident root entries into a newly allocated INDEX_BUFFER via hdr_insert_head(). The source byte count 'to_move' is summed from the on-disk resident entry sizes and is independent of the destination buffer size, which comes from root->index_block_size (via indx->index_bits). A crafted NTFS image that keeps a valid, full resident root but shrinks root->index_block_size down to 512 after the root has been populated makes hdr_insert_head() memcpy attacker-controlled resident entry bytes past the end of the kmalloc(1u << indx->index_bits) allocation returned by indx_new(). For a 512-byte destination and a resident root whose non-last entries total 560 bytes, the memcpy overruns by 120 bytes and a following memmove extends the highest written offset to 136 bytes past the allocation. The overflow bytes are a direct copy of on-disk entries (via kmemdup), so they are fully attacker-controlled. The write is reachable from unprivileged open(O_CREAT) on a mounted crafted NTFS image: a single sufficiently long create in a directory whose resident root is already full forces root promotion and triggers the copy. This is a controlled out-of-bounds write of 120-136 bytes past a kmalloc(index_block_size) allocation, with attacker-controlled content. It is a bounded adjacent-heap corruption primitive; it is not an arbitrary-address write. Successful exploitation into a named victim object depends on the surrounding slab layout. Reject the copy at the sink. The destination's INDEX_HDR already reports hdr_total (the payload capacity of the new buffer) and hdr_used (the bytes already consumed by the terminal END entry installed by indx_new()); require that to_move fits in the remaining payload before calling hdr_insert_head(). On mismatch, fail with -EINVAL and mark the filesystem as having a detected on-disk inconsistency, which is the same behaviour as the surrounding validation in this function. | |
| Title | ntfs3: bound to_move in indx_insert_into_root before hdr_insert_head | |
| First Time appeared |
Linux
Linux linux Kernel |
|
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
|
| References |
|
|
MITRE
Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2026-08-15T05:53:52.634Z
Reserved: 2026-08-09T03:40:39.911Z
Link: CVE-2026-72192
Vulnrichment
No data.
NVD
Status : Received
Published: 2026-08-15T06:21:37.663
Modified: 2026-08-15T06:21:37.663
Link: CVE-2026-72192
Redhat
No data.
OpenCVE Enrichment
No data.