Instituto Nacional de ciberseguridad. Sección Incibe
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CVE-2026-64395

Severity CVSS v4.0:
Pending analysis
Type:
Unavailable / Other
Publication date:
25/07/2026
Last modified:
27/07/2026

Description

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> ksmbd: require source read access for duplicate extents<br /> <br /> FSCTL_DUPLICATE_EXTENTS_TO_FILE passes the source file directly to<br /> vfs_clone_file_range() or vfs_copy_file_range() without checking the SMB<br /> access mask granted to the source handle. A handle opened with attribute<br /> access can consequently be used to copy file contents into an<br /> attacker-readable destination.<br /> <br /> Require FILE_READ_DATA on the source handle before either VFS operation,<br /> matching other ksmbd data-copy paths.

Impact

Vector 3.x
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N CVSS v3.1 Severity and Metrics:

Base Score: 7.50 HIGH
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Attack Vector (AV): Network
Attack Complexity (AC): Low
Privileges Required (PR): None
User Interaction (UI): None
Scope (S): Unchanged
Confidentiality (C): High
Integrity (I): None
Availability (A): None

Base Score 3.x
7.50
Severity 3.x
HIGH

References to Advisories, Solutions, and Tools