Vulnerability in Linux

CVE-2026-64395

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.

EPSS: 0.004 (33.9th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N.

Affected products

References

Frequently asked questions

What is CVE-2026-64395?
CVE-2026-64395 is a high-severity vulnerability in Linux. CVSS score: 7.5/10. Published 2026-07-25.
How severe is CVE-2026-64395?
High severity. CVSS v3 base score is 7.5 out of 10.