CVE-2026-80672
ntfs: fix u16 truncation of restart-area length check
Description
In the Linux kernel, the following vulnerability has been resolved: ntfs: fix u16 truncation of restart-area length check ntfs_check_restart_area() validates that the $LogFile restart area and its trailing log client record array fit within the system page size: u16 ra_ofs, ra_len, ca_ofs; ... ra_len = ca_ofs + le16_to_cpu(ra->log_clients) * sizeof(struct log_client_record); if (ra_ofs + ra_len > le32_to_cpu(rp->system_page_size) || ...) return false; ra_len is u16, but the right-hand side is computed in size_t (sizeof(struct log_client_record) == 160). Both ca_ofs and log_clients come straight from the on-disk restart area. With an on-disk log_clients of 410 the product 410 * 160 = 65600; adding ca_ofs and storing into the u16 ra_len truncates modulo 65536 (e.g. ca_ofs 64 gives ra_len 128), so the "fits in the page" check passes even though the client array described by log_clients extends far beyond the page. ntfs_check_log_client_array() then walks the array bounded only by the on-disk log_clients count: cr = ca + idx; if (cr->prev_client != LOGFILE_NO_CLIENT) ... For log_clients 410 it dereferences records up to ca + 409 * 160, ~64 KiB past the kvzalloc(system_page_size) restart-page buffer -- an out-of-bounds read of attacker-controlled extent, reachable when a crafted NTFS image is mounted (load_and_check_logfile() at mount time). This is the in-kernel analogue of CVE-2022-30789, fixed in the ntfs-3g userspace driver but never in this revived classic driver. Compute the restart-area length in a u32 so the existing bounds check rejects an over-large client array instead of being defeated by the truncation. Widen ra_ofs and ca_ofs to u32 as well: both are loaded from __le16 on-disk fields and every comparison already promotes to int/size_t, so this changes no result and keeps the declaration uniform.
INFO
Published Date :
Aug. 28, 2026, 8:16 a.m.
Last Modified :
Aug. 28, 2026, 8:16 a.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Affected Products
The following products are affected by CVE-2026-80672
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
Solution
- Compute restart area length using u32.
- Widen offset and length variables to u32.
- Update the kernel to include the fix.
- Mount NTFS images after applying the patch.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-80672.
| URL | Resource |
|---|---|
| https://git.kernel.org/stable/c/07a4751ef3ccc8bfd17bfbb16e5003c03161790d | |
| https://git.kernel.org/stable/c/390936fb15053d8d8991ca3a22776e251a5a7f2f |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-80672 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-80672
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-80672 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-80672 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Aug. 28, 2026
Action Type Old Value New Value Added Description In the Linux kernel, the following vulnerability has been resolved: ntfs: fix u16 truncation of restart-area length check ntfs_check_restart_area() validates that the $LogFile restart area and its trailing log client record array fit within the system page size: u16 ra_ofs, ra_len, ca_ofs; ... ra_len = ca_ofs + le16_to_cpu(ra->log_clients) * sizeof(struct log_client_record); if (ra_ofs + ra_len > le32_to_cpu(rp->system_page_size) || ...) return false; ra_len is u16, but the right-hand side is computed in size_t (sizeof(struct log_client_record) == 160). Both ca_ofs and log_clients come straight from the on-disk restart area. With an on-disk log_clients of 410 the product 410 * 160 = 65600; adding ca_ofs and storing into the u16 ra_len truncates modulo 65536 (e.g. ca_ofs 64 gives ra_len 128), so the "fits in the page" check passes even though the client array described by log_clients extends far beyond the page. ntfs_check_log_client_array() then walks the array bounded only by the on-disk log_clients count: cr = ca + idx; if (cr->prev_client != LOGFILE_NO_CLIENT) ... For log_clients 410 it dereferences records up to ca + 409 * 160, ~64 KiB past the kvzalloc(system_page_size) restart-page buffer -- an out-of-bounds read of attacker-controlled extent, reachable when a crafted NTFS image is mounted (load_and_check_logfile() at mount time). This is the in-kernel analogue of CVE-2022-30789, fixed in the ntfs-3g userspace driver but never in this revived classic driver. Compute the restart-area length in a u32 so the existing bounds check rejects an over-large client array instead of being defeated by the truncation. Widen ra_ofs and ca_ofs to u32 as well: both are loaded from __le16 on-disk fields and every comparison already promotes to int/size_t, so this changes no result and keeps the declaration uniform. Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/80xxx/CVE-2026-80672.json">CVE-2026-80672</a> Added Reference https://git.kernel.org/stable/c/07a4751ef3ccc8bfd17bfbb16e5003c03161790d Added Reference https://git.kernel.org/stable/c/390936fb15053d8d8991ca3a22776e251a5a7f2f