CVE-2026-98428

What the bug is

The USB 6fire driver uses URBs embedded in different structs for PCM, MIDI and communication, and this is basically a buggy implementation nowadays; since a URB is managed with a refcount, this may lead to a UAF when the URB is released asynchronously. For addressing the problem, this patch converts those embedded URBs to ones that are properly allocated via usb_alloc_urb(). The pcm_urb.packets[] is gone, as it's allocated by usb_alloc_urb(), hence it's found in urb.iso_frame_desc[] instead. The conversions are rather straightforward; each embedded struct urb is changed to a pointer, and its callers are updated accordingly. The resource for those structs are released in the common destructor functions (usb6fire_comm_free(), etc), which are called at both the init error path and the disconnect. No functional changes, only compile-tested.

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.

sound/usb/6fire/comm.c
sound/usb/6fire/comm.h
sound/usb/6fire/midi.c
sound/usb/6fire/midi.h
sound/usb/6fire/pcm.c
sound/usb/6fire/pcm.h

What this is

SOUNDMAINTAINERS section matched on sound/ · linux-sound@vger.kernel.org · Maintained

Kernel module

snd_usb_6fire

Check it on the machine

grep -wE 'CONFIG_SND|CONFIG_SND_USB_6FIRE' /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 snd_usb_6fire

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 builds this, but not on every flavour. At least one release below builds the code on some of its kernel flavours and not on others, so the answer depends on the architecture and flavour installed.

• bookworm, trixie, forky, sidMnot built on amd64/cloud-amd64, arm64/cloud-arm64

M

a module where it is built at all; some flavours do not build it

Build switches

CONFIG_SND, CONFIG_SND_USB_6FIRE

Reads as

all on means the file is compiled; any one off means it is not.

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

2026-10-14 (4 days ago)source

CVSS

no vector published, unrated

Attack vector

not published

EPSS

0.21%, higher than 11.1% of all CVEssource

CISA KEV

not listedthe KEV catalogue

Debian urgency

not yet assignedsource

Subsystem

sound/usb

Upstream fixes

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

Introduced	Fixed in	Commit
0	6.1.189	3ef9093d83ff
0	6.6.158	8b8559aeaba2
0	6.12.112	52a43c2d57e7
0	6.18.54	999f433c09e4
0	7.2.8	d181434549b3
0	7.3	9fe49dbc023e

Debian advisories