CVE-2026-64483

What the bug is

isight_packet() takes the frame count from the device iso packet and checks it only against the device claimed iso length. count = be32_to_cpu(payload->sample_count); if (likely(count <= (length - 16) / 4)) isight_samples(isight, payload->samples, count); length is the iso header data_length. It can be up to 0xffff. So the gate allows a count up to about 16379. isight_samples() then copies count frames out of payload->samples into the PCM DMA buffer. payload->samples holds only 2 * MAX_FRAMES_PER_PACKET values. The device multiplexes two samples per frame. A count past MAX_FRAMES_PER_PACKET reads past the payload. A count past the buffer size writes past runtime->dma_area. The smallest PCM buffer is larger than MAX_FRAMES_PER_PACKET. Bounding the count to MAX_FRAMES_PER_PACKET keeps both the read and the write in range. A malicious or faulty Apple iSight on the FireWire bus reaches this during a normal capture. Add the MAX_FRAMES_PER_PACKET bound to the gate.

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/firewire/isight.c

What this is

FIREWIRE AUDIO DRIVERS and IEC 61883-1/6 PACKET STREAMING ENGINEMAINTAINERS section matched on sound/firewire/ · linux-sound@vger.kernel.org · Maintained

Kernel module

snd_isight

Check it on the machine

grep -wE 'CONFIG_SND|CONFIG_SND_ISIGHT' /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_isight

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.

• bookwormMnot built on amd64/cloud-amd64, arm64/cloud-arm64
• trixieMnot built on amd64/cloud-amd64, arm64/cloud-arm64, armel/rpi
• forky, sid, bookworm · linux-6.12Mnot 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_ISIGHT

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

2026-07-25 (3 months ago)source

CVSS

no vector published, unrated

Attack vector

not published

EPSS

0.18%, higher than 7.5% of all CVEssource

CISA KEV

not listedthe KEV catalogue

Debian urgency

not yet assignedsource

Subsystem

sound/firewire

Upstream fixes

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

Introduced	Fixed in	Commit
3.0	5.10.261	24423e0a9251
3.0	5.15.212	ebbffacda673
3.0	6.1.178	57e4d9043afc
3.0	6.6.145	3ed2fa1ed8cc
3.0	6.12.96	31da82b9676c
3.0	6.18.39	8e48a29813df
3.0	7.1.4	31a01b70bb90
3.0	7.2	29b9667982e4

Debian advisories