CVE-2026-97995

What the bug is

__send_control_msg() publishes &portdev->cpkt as the control-out virtqueue cookie. remove_vqs() walks every virtqueue and passes leftover cookies to free_buf(), which treats them as struct port_buffer and reads sgpages. If a control message is still on c_ovq when the device is unbound, free_buf() reads past the ports_device object. KASAN reported slab-out-of-bounds in free_buf(): free_buf remove_vqs virtcons_remove unbind_store The object was the ports_device allocated in virtcons_probe(). Drain c_ovq without freeing. The packet lives in portdev and is released with it.

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/char/virtio_console.c

What this is

VIRTIO CONSOLE DRIVERMAINTAINERS section matched on drivers/char/virtio_console.c · virtualization@lists.linux.dev · Maintained

Kernel module

virtio_console

Check it on the machine

grep -w CONFIG_VIRTIO_CONSOLE /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 virtio_console

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 code. Every release below compiles the affected file into the kernels it ships.

• bookwormm
• trixie, forky, sid, bookworm · linux-6.12y

m

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

y

built into the kernel image on every flavour - only a patch removes it

Build switch

CONFIG_VIRTIO_CONSOLE

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

2026-09-25 (24 days ago)source

CVSS

no vector published, unrated

Attack vector

not published

EPSS

0.18%, higher than 6.7% of all CVEssource

CISA KEV

not listedthe KEV catalogue

Debian urgency

not yet assignedsource

Subsystem

drivers/char

Upstream fixes

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

Introduced	Fixed in	Commit
4.17	5.10.271	b1f39c2a6766
4.17	5.15.222	e03522a990cd
4.17	6.1.189	8f6cfc3eca79
4.17	6.6.158	2e40c69b9c34
4.17	6.12.111	177ee901aa2b
4.17	6.18.53	a80c33488e0b
4.17	7.2.7	f620c40ea686
4.17	7.3	894f98e73983
3.16.60	0	0
3.18.108	0	0
4.1.52	0	0
4.4.131	0	0
4.9.98	0	0
4.14.39	0	0
4.16.7	0	0

Debian advisories