CVE-2026-98761

What the bug is

Reset the port if the tcpm fails to start the FAST_ROLE_SWAP AMS by initiating error recovery on it. This helps in cases where some cables (incorrectly) signal an FRS to an FRS capable port during disconnection. The TCPC autonomously starts sourcing VBUS on detecting the FRS signal. However, the VBUS sourcing is left on when the FAST_ROLE_SWAP AMS fails to start (as tcpm_sink_tx_ok is 0 as CC is open due to the cable disconnect). This is because the code sets the state to INVALID_STATE without resetting the port state. Log snippet before changes: [ 101.401960] AMS FAST_ROLE_SWAP start [ 101.401971] Sink TX No Go [ 101.401982] sourcing vbus [ 101.401987] VBUS on [ 101.402159] VBUS on [ 109.257809] CC1: 0 -> 0, CC2: 5 -> 0 [state SNK_READY, polarity 1, disconnected] [ 111.267442] VBUS on After changes: [ 70.541211] AMS FAST_ROLE_SWAP start [ 70.541220] Sink TX No Go [ 70.541228] state change SNK_READY -> ERROR_RECOVERY [rev3 NONE_AMS] [ 70.541362] VBUS on [ 70.541365] sourcing vbus [ 70.541367] VBUS on [ 70.541374] state change ERROR_RECOVERY -> PORT_RESET [rev3 NONE_AMS] [ 70.541410] disable vbus discharge ret:0 [ 70.543028] Setting usb_comm capable false [ 70.544009] Setting voltage/current limit 0 mV 0 mA [ 70.544034] polarity 0 [ 70.544239] Requesting mux state 0, usb-role 0, orientation 0 [ 70.555550] cc:=0 [ 70.555595] pending state change PORT_RESET -> PORT_RESET_WAIT_OFF @ 100 ms [rev3 NONE_AMS] [ 70.555697] VBUS off [ 70.555702] VBUS VSAFE0V [ 70.555762] CC1: 5 -> 0, CC2: 0 -> 0 [state PORT_RESET, polarity 0, disconnected] [ 70.587794] VBUS off [ 70.587799] VBUS VSAFE0V [ 70.655672] state change PORT_RESET -> PORT_RESET_WAIT_OFF [delayed 100 ms] [ 70.655682] state change PORT_RESET_WAIT_OFF -> SNK_UNATTACHED [rev3 NONE_AMS] [ 70.655686] Start toggling [ 70.656274] CC1: 0 -> 0, CC2: 0 -> 0 [state TOGGLING, polarity 0, disconnected]

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/tcpm/tcpm.c

What this is

USB TYPEC PORT CONTROLLER DRIVERSMAINTAINERS section matched on drivers/usb/typec/tcpm/tcpm.c · linux-usb@vger.kernel.org · Maintained

Kernel module

tcpm

Check it on the machine

grep -wE 'CONFIG_OF|CONFIG_PCI|CONFIG_TYPEC|CONFIG_TYPEC_TCPM|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.

lsmod | grep -w tcpm

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/amd64, amd64/cloud-amd64, amd64/rt/amd64, arm64/cloud-arm64, armhf/armmp, armhf/armmp-lpae, armhf/rt/armmp, i386/686, i386/686-pae, i386/rt/686-pae, ppc64el/powerpc64le
• trixieMnot built on amd64/amd64, amd64/cloud-amd64, amd64/rt/amd64, arm64/cloud-arm64, armel/rpi, armhf/armmp, armhf/armmp-lpae, armhf/rt/armmp, ppc64el/powerpc64le, ppc64el/powerpc64le-64k, riscv64/riscv64, s390x/s390x
• forky, sidMnot built on amd64/amd64, amd64/cloud-amd64, amd64/rt-amd64, arm64/cloud-arm64, armhf/armmp, armhf/armmp-lpae, loong64/loong64, ppc64el/powerpc64le, ppc64el/powerpc64le-64k, riscv64/riscv64, s390x/s390x

M

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

Build switches

CONFIG_OF, CONFIG_PCI, CONFIG_TYPEC, CONFIG_TYPEC_TCPM, 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

2026-10-18 (today)source

CVSS

no vector published, unrated

Attack vector

not published

EPSS

not scored

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
5.12	6.12.113	184d842121e7
5.12	6.18.56	b2ed8643face
5.12	7.2.10	d6b0cce61263
5.12	7.3	90156585765b