CVE-2026-80674

What the bug is

A base inode's $ATTRIBUTE_LIST is sanity-checked by load_attribute_list() only on the non-resident path; ntfs_read_locked_inode() copies a *resident* attribute list into ni->attr_list with a plain memcpy() and no validation at all. Every subsequent walk of ni->attr_list -- ntfs_external_attr_find(), ntfs_inode_attach_all_extents() and ntfs_attrlist_need() -- then trusts the entries are well-formed and reads attr_list_entry fixed-header fields (lowest_vcn at offset 8, mft_reference at offset 16, and the name) with bounds that assume validation already happened. A crafted resident attribute list therefore reaches those walks unvalidated and can drive out-of-bounds reads of the attribute-list buffer. load_attribute_list() itself reads ale->name_offset (offset 7), ale->mft_reference (offset 16) and the name length under only an "al < al_start + size" bound, so its own validation loop can over-read the fixed header of a truncated trailing entry by a few bytes. Factor the per-entry validation into ntfs_attr_list_entry_is_valid(), which requires each entry's fixed header (offsetof(struct attr_list_entry, name)) to be in range before any field is dereferenced, that ale->length is a multiple of 8 covering the fixed header plus the name, and that the entry is in use and carries a live MFT reference. ntfs_attr_list_is_valid() walks the buffer with it and checks the entries tile it exactly. Use the list validator in load_attribute_list() (replacing the open-coded loop, closing its own over-read) and on the resident path in ntfs_read_locked_inode() (which previously skipped validation entirely); patches 2/3 reuse the per-entry helper at the other two attribute-list walks.

Where it lives

The fix touches these files. If the subsystem is one you do not use, the practical exposure is lower, though the package is still the vulnerable one.

fs/ntfs/attrib.c
fs/ntfs/attrib.h
fs/ntfs/inode.c

What this is

NTFS FILESYSTEMMAINTAINERS section matched on fs/ntfs/ · linux-fsdevel@vger.kernel.org · Maintained

Kernel module

ntfs

Check it on the machine

grep -w CONFIG_NTFS_FS /boot/config-$(uname -r)

Reads the booted kernel's own configuration, on the machine and nowhere else. =y is built in, =m is a module, and an is not set line means the code is not there.

lsmod | grep -w ntfs

Prints a line if that module is loaded right now, and nothing if it is not. One that is not loaded can still be loaded later by anything that needs it.

Show whether Debian builds this, per release

Debian does not build this code in 1 release. It does build it in 2 releases, so the answer depends on which release the machine runs. The build rule could not be established for 1 release, so nothing is claimed about those.

• bookwormn
• trixie?
• forky, sidm

n

not enabled on any flavour - this release does not build the code

?

not established - no Makefile entry for the affected file

m

a loadable module on every flavour - check lsmod, can be blacklisted

Where a release above reads "not established", no build rule for the affected file was found in that release's kernel tree. That is a gap in this lookup, not a finding that the code is absent.

Build switch

CONFIG_NTFS_FS

From the configuration Debian publishes for every kernel flavour it builds. It covers only the architectures Debian ships a linux-config package for, and nothing about a kernel you built yourself. Debian's own status above stays authoritative about the source package.MAINTAINERS kbuild Makefiles Debian linux-config packages

Signals

Published

2026-08-28 (2 months ago)source

CVSS

9.8 critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hsource recompute it

Attack vector

network (AV:N)source

EPSS

0.55%, higher than 45.0% of all CVEssource

CISA KEV

not listedthe KEV catalogue

Debian urgency

unimportantsource

Subsystem

fs/ntfs

Upstream fixes

The versions the CNA records as introducing and fixing this, and the commit for each. source

Introduced	Fixed in	Commit
7.1	7.1.5	55e97648f775
7.1	7.2	7d19e1ffee08