CVE-2025-68786
ksmbd: skip lock-range check on equal size to avoid size==0 underflow
Description
In the Linux kernel, the following vulnerability has been resolved: ksmbd: skip lock-range check on equal size to avoid size==0 underflow When size equals the current i_size (including 0), the code used to call check_lock_range(filp, i_size, size - 1, WRITE), which computes `size - 1` and can underflow for size==0. Skip the equal case.
INFO
Published Date :
Jan. 13, 2026, 4:15 p.m.
Last Modified :
Jan. 13, 2026, 4:15 p.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Solution
- Update the Linux kernel to the latest stable version.
- Apply the ksmbd patch to prevent size underflow.
- Recompile the kernel if necessary.
- Reboot the system after updating.
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-2025-68786.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2025-68786 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-2025-68786
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-2025-68786 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2025-68786 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.
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New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Jan. 13, 2026
Action Type Old Value New Value Added Description In the Linux kernel, the following vulnerability has been resolved: ksmbd: skip lock-range check on equal size to avoid size==0 underflow When size equals the current i_size (including 0), the code used to call check_lock_range(filp, i_size, size - 1, WRITE), which computes `size - 1` and can underflow for size==0. Skip the equal case. Added Reference https://git.kernel.org/stable/c/52fcbb92e0d3acfd1448b2a43b6595d540da5295 Added Reference https://git.kernel.org/stable/c/571204e4758a528fbd67330bd4b0dfbdafb33dd8 Added Reference https://git.kernel.org/stable/c/5d510ac31626ed157d2182149559430350cf2104 Added Reference https://git.kernel.org/stable/c/a6f4cfa3783804336491e0edcb250c25f9b59d33 Added Reference https://git.kernel.org/stable/c/da29cd197246c85c0473259f1cad897d9d28faea