CVE-2026-64395

Name	CVE-2026-64395
Description	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.
Source	CVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)
References	DLA-4720-1, DLA-4723-1, DLA-4724-1

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
linux (PTS)	bullseye	5.10.223-1	fixed
	bullseye (security)	5.10.262-1	fixed
	bookworm	6.1.176-1	vulnerable
	bookworm (security)	6.1.180-1	fixed
	trixie	6.12.94-1	vulnerable
	trixie (security)	6.12.101-1	fixed
	forky	7.1.7-1	fixed
	sid	7.1.8-1	fixed
linux-6.1 (PTS)	bullseye (security)	6.1.180-1~deb11u1	fixed
linux-6.12 (PTS)	bookworm (security)	6.12.100-1~deb12u1	fixed

The information below is based on the following data on fixed versions.

Package	Type	Release	Fixed Version	Origin
linux	source	bullseye	(not affected)
linux	source	bookworm	6.1.180-1	DLA-4720-1
linux	source	trixie	6.12.96-1
linux	source	(unstable)	7.1.4-1
linux-6.1	source	bullseye	6.1.180-1~deb11u1	DLA-4723-1
linux-6.12	source	bookworm	6.12.100-1~deb12u1	DLA-4724-1

[bullseye] - linux <not-affected> (Vulnerable code not present)
https://git.kernel.org/linus/cedff600f1642aa982178503552f0d007bc829c8 (7.2-rc1)