Description
In the Linux kernel, the following vulnerability has been resolved:
ntfs3: fix out-of-bounds read in ntfs_dir_emit() and hdr_find_e()
The bounds check in ntfs_dir_emit() compares fname->name_len (a
character count) against e->size (a byte count) without accounting
for the 2-byte-per-character UTF-16LE encoding or the ATTR_FILE_NAME
header size:
if (fname->name_len + sizeof(struct NTFS_DE) > le16_to_cpu(e->size))
This computes: name_len + 16 > e_size
The correct check must account for the ATTR_FILE_NAME header (66 bytes
before the name) and the UTF-16LE character size (2 bytes each):
sizeof(NTFS_DE) + offsetof(ATTR_FILE_NAME, name) +
name_len * sizeof(short) > e_size
Which computes: 16 + 66 + name_len * 2 > e_size
The correct calculation already exists as fname_full_size() in ntfs.h
and is used in cmp_fnames(), namei.c, and fslog.c, but was not used
in the readdir path.
A crafted NTFS image with an index entry containing a small e->size
but large fname->name_len bypasses the current check, causing
ntfs_utf16_to_nls() to read past the entry boundary.
Additionally, add a key_size validation in hdr_find_e() to ensure the
declared key_size does not exceed the available entry data, preventing
comparison functions from reading past entry boundaries on the lookup
path.
ntfs3: fix out-of-bounds read in ntfs_dir_emit() and hdr_find_e()
The bounds check in ntfs_dir_emit() compares fname->name_len (a
character count) against e->size (a byte count) without accounting
for the 2-byte-per-character UTF-16LE encoding or the ATTR_FILE_NAME
header size:
if (fname->name_len + sizeof(struct NTFS_DE) > le16_to_cpu(e->size))
This computes: name_len + 16 > e_size
The correct check must account for the ATTR_FILE_NAME header (66 bytes
before the name) and the UTF-16LE character size (2 bytes each):
sizeof(NTFS_DE) + offsetof(ATTR_FILE_NAME, name) +
name_len * sizeof(short) > e_size
Which computes: 16 + 66 + name_len * 2 > e_size
The correct calculation already exists as fname_full_size() in ntfs.h
and is used in cmp_fnames(), namei.c, and fslog.c, but was not used
in the readdir path.
A crafted NTFS image with an index entry containing a small e->size
but large fname->name_len bypasses the current check, causing
ntfs_utf16_to_nls() to read past the entry boundary.
Additionally, add a key_size validation in hdr_find_e() to ensure the
declared key_size does not exceed the available entry data, preventing
comparison functions from reading past entry boundaries on the lookup
path.
Published:
2026-09-24
Score:
n/a
EPSS:
n/a
KEV:
No
Impact:
n/a
Action:
n/a
Analysis and contextual insights are available on OpenCVE Cloud.
Remediation
No vendor fix or workaround currently provided.
Additional remediation guidance may be available on OpenCVE Cloud.
Tracking
Sign in to view the affected projects.
Advisories
No advisories yet.
References
History
Thu, 24 Sep 2026 16:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | In the Linux kernel, the following vulnerability has been resolved: ntfs3: fix out-of-bounds read in ntfs_dir_emit() and hdr_find_e() The bounds check in ntfs_dir_emit() compares fname->name_len (a character count) against e->size (a byte count) without accounting for the 2-byte-per-character UTF-16LE encoding or the ATTR_FILE_NAME header size: if (fname->name_len + sizeof(struct NTFS_DE) > le16_to_cpu(e->size)) This computes: name_len + 16 > e_size The correct check must account for the ATTR_FILE_NAME header (66 bytes before the name) and the UTF-16LE character size (2 bytes each): sizeof(NTFS_DE) + offsetof(ATTR_FILE_NAME, name) + name_len * sizeof(short) > e_size Which computes: 16 + 66 + name_len * 2 > e_size The correct calculation already exists as fname_full_size() in ntfs.h and is used in cmp_fnames(), namei.c, and fslog.c, but was not used in the readdir path. A crafted NTFS image with an index entry containing a small e->size but large fname->name_len bypasses the current check, causing ntfs_utf16_to_nls() to read past the entry boundary. Additionally, add a key_size validation in hdr_find_e() to ensure the declared key_size does not exceed the available entry data, preventing comparison functions from reading past entry boundaries on the lookup path. | |
| Title | ntfs3: fix out-of-bounds read in ntfs_dir_emit() and hdr_find_e() | |
| First Time appeared |
Linux
Linux linux Kernel |
|
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
|
| References |
|
Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2026-09-24T16:03:50.105Z
Reserved: 2026-09-24T14:53:16.869Z
Link: CVE-2026-97437
No data.
Status : Received
Published: 2026-09-24T17:17:21.810
Modified: 2026-09-24T17:17:21.810
Link: CVE-2026-97437
No data.
OpenCVE Enrichment
No data.
Weaknesses
No weakness.