CVE-2026-64329

What the bug is

The threaded IRQ handler ccg_irq_handler() calls ucsi_notify_common(), which on a connector-change event calls ucsi_connector_change() and schedules connector work. In ucsi_ccg_remove(), ucsi_destroy() frees uc->ucsi (kfree) before free_irq() is called, so a handler invocation already in flight may access the freed object after ucsi_destroy(). CPU 0 (remove) | CPU 1 (threaded IRQ) ucsi_destroy(uc->ucsi) | ccg_irq_handler() kfree(ucsi) // FREE | ucsi_notify_common(uc->ucsi) // USE Move free_irq() before ucsi_destroy() in the remove path. It is kept after ucsi_unregister(): ucsi_unregister() cancels connector work whose handler issues GET_CONNECTOR_STATUS through ucsi_send_command_common(), which waits for a completion that is signalled from the IRQ handler, so the IRQ must stay active until that work has been cancelled. The probe error path already orders free_irq() before ucsi_destroy(). This bug was found by static analysis.

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/usb/typec/ucsi/ucsi_ccg.c

What this is

USB TYPEC CLASSMAINTAINERS section matched on drivers/usb/typec/ · linux-usb@vger.kernel.org · Maintained

Kernel module

none to look for. The file would have gone into ucsi_ccg, and Debian does not compile it into that module, so finding ucsi_ccg in lsmod would say nothing about this CVE.

Check it on the machine

grep -wE 'CONFIG_OF|CONFIG_PCI|CONFIG_TYPEC|CONFIG_TYPEC_UCSI|CONFIG_UCSI_CCG|CONFIG_USB|CONFIG_USB_GADGET|CONFIG_USB_PHY|CONFIG_USB_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.

Show whether Debian builds this, per release

Debian does not build this code. In 5 releases below, every kernel flavour Debian publishes has the switch off, so the vulnerable file is compiled into no kernel binary Debian ships.

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

n

not enabled on any flavour - this release does not build the code

Build switches

CONFIG_OF, CONFIG_PCI, CONFIG_TYPEC, CONFIG_TYPEC_UCSI, CONFIG_UCSI_CCG, CONFIG_USB, CONFIG_USB_GADGET, CONFIG_USB_PHY, CONFIG_USB_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

2026-07-25 (3 months ago)source

CVSS

no vector published, unrated

Attack vector

not published

EPSS

0.13%, higher than 2.0% of all CVEssource

CISA KEV

not listedthe KEV catalogue

Debian urgency

not yet assignedsource

Subsystem

drivers/usb

Upstream fixes

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

Introduced	Fixed in	Commit
5.5	5.10.261	f1adeb1ff8be
5.5	5.15.212	99381e762273
5.5	6.1.178	1a160076d3d0
5.5	6.6.145	c32df1114782
5.5	6.12.96	86c9ee928c4a
5.5	6.18.39	f5c772b76bbd
5.5	7.1.4	dbb500bad021
5.5	7.2	1f0bdc2884b6

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