CVE-2026-80783

What the bug is

magicmouse_raw_event() handles DOUBLE_REPORT_ID (0xf7) packets, which pack two touch reports into one, by splitting the packet and calling itself on each half. The only guard against runaway recursion is a "size < 1" check, which stops zero-sized calls but does not bound the recursion depth. A malicious HID device that matches this driver can send a report starting with DOUBLE_REPORT_ID and filled with the sequence [0xf7, 0x00]. Each level consumes two bytes and recurses on the remainder, so an incoming report of up to HID_MAX_BUFFER_SIZE (16 KiB) drives roughly 8000 nested calls. That easily exhausts the 16 KiB kernel stack, leading to a stack overflow: a panic with CONFIG_VMAP_STACK, or memory corruption without it. A double report only ever wraps two normal reports; it is never legitimately nested. Refuse to re-enter the DOUBLE_REPORT_ID case from a recursive call so the recursion depth is bounded to two, while all valid packets keep being parsed exactly as before.

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.

drivers/hid/hid-magicmouse.c

What this is

HID CORE LAYERMAINTAINERS section matched on drivers/hid/ · linux-input@vger.kernel.org · Maintained

Kernel module

hid_magicmouse

Check it on the machine

grep -wE 'CONFIG_HID|CONFIG_HID_MAGICMOUSE|CONFIG_HID_SUPPORT' /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 hid_magicmouse

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, trixieMnot built on arm64/cloud-arm64
• forky, sidMnot built on amd64/cloud-amd64, arm64/cloud-arm64
• bookworm · linux-6.12Mnot built on arm64/cloud-arm64

M

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

Build switches

CONFIG_HID, CONFIG_HID_MAGICMOUSE, CONFIG_HID_SUPPORT

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

2026-09-04 (44 days ago)source

CVSS

no vector published, unrated

Attack vector

not published

EPSS

0.19%, higher than 8.6% of all CVEssource

CISA KEV

not listedthe KEV catalogue

Debian urgency

not yet assignedsource

Subsystem

drivers/hid

Upstream fixes

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

Introduced	Fixed in	Commit
2.6.37	5.15.220	26c45abed625
2.6.37	6.1.187	8a10a624996f
2.6.37	6.6.156	d16df755b449
2.6.37	6.12.108	bec338b07beb
2.6.37	6.18.49	70589b0c005d
2.6.37	7.1.11	a33a596d3ad8
2.6.37	7.2.1	d095de37f78c
2.6.37	7.3	db8d634128d2

Debian advisories