CVE-2026-93091

What the bug is

scmi_notification_exit() clears and releases the notification instance, but transport callbacks can still deliver incoming notifications until the TX/RX channels are freed. During remove, an RX interrupt in that window can enter scmi_notify() while notification state is being torn down and then dereference freed memory. The same ordering exists on the probe error path after notification initialization. The notification late-init worker has a separate lifetime issue: protocol event registration queues ni->init_work on the system workqueue, so destroying ni->notify_wq does not drain that work. If the devres group is released while init_work is still pending or running, the late-init worker can dereference the freed notification instance. Quiesce the notification core before TX/RX channels are torn down, then clean up the channels before releasing the notification core resources. Use disable_work_sync() so future late-init queueing is rejected and any already queued or running late-init work has completed before channel teardown starts.

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/firmware/arm_scmi/driver.c
drivers/firmware/arm_scmi/notify.c
drivers/firmware/arm_scmi/notify.h

What this is

SYSTEM CONTROL & POWER/MANAGEMENT INTERFACE (SCPI/SCMI) Message Protocol driversMAINTAINERS section matched on drivers/firmware/arm_scmi/ · arm-scmi@vger.kernel.org · Maintained

Show whether Debian builds this, per release

Not established. This site could not find the build rule for the affected file in the kernel trees Debian ships, so it has no answer about whether Debian compiles this code. Read that as unknown, never as absent.

• bookworm, trixie, forky, sid, bookworm · linux-6.12?

?

not established - no Makefile entry for the affected file

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.

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

Signals

Published

2026-09-17 (31 days ago)source

CVSS

no vector published, unrated

Attack vector

not published

EPSS

0.21%, higher than 10.3% of all CVEssource

CISA KEV

not listedthe KEV catalogue

Debian urgency

not yet assignedsource

Subsystem

drivers/firmware

Upstream fixes

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

Introduced	Fixed in	Commit
5.15	6.12.110	6778bcabd2e0
5.15	6.18.52	2aac23bc0a79
5.15	7.2.6	5e30d3d16d1a
5.15	7.3	8e49055d0d49

Debian advisories