CVE-2026-64395

CVE-2026-64395

High · published July 25, 2026

CVSS v3.1
7.5
EPSS
0%
Percentile
33.8
In the wild
Unconfirmed
What it is

In the Linux kernel, the following vulnerability has been resolved:

ksmbd: require source read access for duplicate extents

FSCTL_DUPLICATE_EXTENTS_TO_FILE passes the source file directly to

vfs_clone_file_range() or vfs_copy_file_range() without checking the SMB

access mask granted to the source handle. A handle opened with attribute

access can consequently be used to copy file contents into an

attacker-readable destination.

Require FILE_READ_DATA on the source handle before either VFS operation,

matching other ksmbd data-copy paths.

The record
Technical detail
CVSS v3.1
7.5 · HIGH
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
CVSS v4.0
Not supplied
EPSS
0.00406 · 33.8th percentile
Published
2026-07-25T14:17Z
Affected products (5)
ProductVersionsFixed in
linux/linux_kernel≥ 5.15, < 6.1.1786.1.178
linux/linux_kernel≥ 6.2, < 6.6.1456.6.145
linux/linux_kernel≥ 6.7, < 6.12.966.12.96
linux/linux_kernel≥ 6.13, < 6.18.396.18.39
linux/linux_kernel≥ 6.19, < 7.1.47.1.4
References (6)
EPSS history
Timeline
  • 25 JUL 08:50Z
    ksmbd: require source read access for duplicate extents
    cvelistv5