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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-64399 Detail

Description

In the Linux kernel, the following vulnerability has been resolved: ksmbd: add permission checks for FSCTL_DUPLICATE_EXTENTS_TO_FILE The FSCTL_DUPLICATE_EXTENTS_TO_FILE arm of smb2_ioctl() overwrites the destination file's data via vfs_clone_file_range() with neither the share-level KSMBD_TREE_CONN_FLAG_WRITABLE check nor a per-handle fp->daccess check that the other write-bearing arms carry. A client can overwrite destination data on a read-only share, or from a handle opened with only FILE_WRITE_ATTRIBUTES (which still yields an FMODE_WRITE filp). FILE_WRITE_ATTRIBUTES-only destination handle overwrote the file's data via the clone. Add both checks, matching the FSCTL_SET_SPARSE permission fix; require FILE_WRITE_DATA since this writes data.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

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URL Source(s) Tag(s)
https://git.kernel.org/stable/c/388e4139db27a9e3612c9d356b826f5b1ff6a9e3 kernel.org
https://git.kernel.org/stable/c/620d133d469295ee7c017ca6aafac335f65c4a5a kernel.org
https://git.kernel.org/stable/c/9b9cf7e65cbeaae1b6636144bacee611cdd7a5d6 kernel.org
https://git.kernel.org/stable/c/baae7b39673ec21073a25e3d14f8feaada01d5df kernel.org
https://git.kernel.org/stable/c/bf460ad5958d506492de4524a656439da3f99c51 kernel.org
https://git.kernel.org/stable/c/c917e4522d251071dde9871b9142d8ea1186ebfe kernel.org

Weakness Enumeration

CWE-ID CWE Name Source

Change History

1 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-64399
NVD Published Date:
07/25/2026
NVD Last Modified:
07/25/2026
Source:
kernel.org