CVE-2026-64330

What the bug is

In svdm_consume_modes(), the SVID value is read from pmdata->svids using pmdata->svid_index as an array index without bounds validation: paltmode->svid = pmdata->svids[pmdata->svid_index]; If pmdata->svid_index is driven beyond SVID_DISCOVERY_MAX (16), it results in an out-of-bounds read of the pmdata->svids array. Because pd_mode_data is embedded inside struct tcpm_port, indexing past svids reads into adjacent fields. In particular: - At index 16, it reads the altmodes count. - At index 18 and beyond, it reads into altmode_desc[], which contains partner-supplied SVDM Discovery Modes VDOs. By injecting a chosen SVID into altmode_desc[0].vdo and driving svid_index to 20, the partner can force paltmode->svid to be loaded with an arbitrary, partner- chosen SVID, which is then registered via typec_partner_register_altmode(). Fix this by validating that pmdata->svid_index is non-negative and strictly less than pmdata->nsvids before accessing the pmdata->svids array inside svdm_consume_modes().

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
• bookworm · linux-6.12Mnot built on amd64/amd64, amd64/cloud-amd64, amd64/rt/amd64, arm64/cloud-arm64, armhf/armmp, armhf/armmp-lpae, armhf/rt/armmp, ppc64el/powerpc64le, ppc64el/powerpc64le-64k

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

2026-07-25 (3 months ago)source

CVSS

no vector published, unrated

Attack vector

not published

EPSS

0.13%, higher than 2.3% 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
4.19	5.10.261	89ff289cbf5d
4.19	5.15.212	d638ec188e95
4.19	6.1.178	f8163c414de8
4.19	6.6.145	012406f89abc
4.19	6.12.96	c6d2af3b217a
4.19	6.18.39	3e1b1ac47e81
4.19	7.1.4	313ca06e7e22
4.19	7.2	7b681dd5fbf6

Debian advisories