CVE-2026-64549

What the bug is

bpa10x_setup() sends the vendor command 0xfc0e and passes the response to bt_dev_info() and hci_set_fw_info() as a "%s" string starting at skb->data + 1, without checking the length: bt_dev_info(hdev, "%s", (char *)(skb->data + 1)); hci_set_fw_info(hdev, "%s", skb->data + 1); A device that returns a one-byte response (status only) leaves skb->data + 1 past the end of the data, and the %s walk reads adjacent slab memory until it meets a NUL. The same happens when the payload is not NUL-terminated within skb->len. The out-of-bounds bytes end up in the kernel log and the firmware-info debugfs file. Print the revision string with a bounded "%.*s" limited to skb->len - 1 instead. This keeps the string readable for well-behaved devices while never reading past the received data, and does not fail setup, so a device returning a short or unterminated response keeps working.

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/bluetooth/bpa10x.c

What this is

BLUETOOTH DRIVERSMAINTAINERS section matched on drivers/bluetooth/ · linux-bluetooth@vger.kernel.org · Supported

Kernel module

bpa10x

Check it on the machine

grep -wE 'CONFIG_BT|CONFIG_BT_HCIBPA10X' /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 bpa10x

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/cloud-amd64, arm64/arm64, arm64/cloud-arm64, arm64/rt/arm64, armhf/armmp, armhf/armmp-lpae, armhf/rt/armmp
• trixieMnot built on amd64/cloud-amd64, arm64/arm64, arm64/arm64-16k, arm64/cloud-arm64, arm64/rt/arm64, armel/rpi, armhf/armmp, armhf/armmp-lpae, armhf/rt/armmp, riscv64/riscv64, s390x/s390x
• forky, sidMnot built on amd64/cloud-amd64, arm64/arm64, arm64/arm64-16k, arm64/cloud-arm64, arm64/rt-arm64, armhf/armmp, armhf/armmp-lpae, riscv64/riscv64, s390x/s390x
• bookworm · linux-6.12Mnot built on amd64/cloud-amd64, arm64/arm64, arm64/arm64-16k, arm64/cloud-arm64, arm64/rt/arm64, armhf/armmp, armhf/armmp-lpae, armhf/rt/armmp

M

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

Build switches

CONFIG_BT, CONFIG_BT_HCIBPA10X

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

2026-07-27 (3 months ago)source

CVSS

no vector published, unrated

Attack vector

not published

EPSS

0.18%, higher than 7.1% of all CVEssource

CISA KEV

not listedthe KEV catalogue

Debian urgency

not yet assignedsource

Subsystem

drivers/bluetooth

Upstream fixes

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

Introduced	Fixed in	Commit
4.4	5.10.261	1813add71e38
4.4	5.15.212	bd56c23f1f86
4.4	6.1.178	7a64f39ebe1b
4.4	6.6.145	f80b4afe893d
4.4	6.12.97	4b4008dda1d0
4.4	6.18.40	bfc9e7be289d
4.4	7.1.5	a8e169d30877
4.4	7.2	dd068ef04412

Debian advisories