PT-2026-64616 · Linux · Linux

CVE-2026-64395 · Published 2026-07-25 · Updated 2026-07-25

Mitre

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.

Related Identifiers

CVE-2026-64395

Affected Products

Linux

References · 7

• https://nvd.nist.gov/vuln/detail/CVE-2026-64395 · Security Note
• https://git.kernel.org/stable/c/a10942af27832c2761d020863a46e79bebe0567d · Note
• https://git.kernel.org/stable/c/67bdad9cf01b25030e3bf00bbce6c309319d6663 · Note
• https://git.kernel.org/stable/c/2d2ab6983620c2d60ce7db72133984ca3873b929 · Note
• https://git.kernel.org/stable/c/db231af842868268839f9f9619c68cb27830d8be · Note
• https://git.kernel.org/stable/c/b0d4d5cb846a1ddb7aaab9adfb5986e4540e6e5f · Note
• https://git.kernel.org/stable/c/cedff600f1642aa982178503552f0d007bc829c8 · Note