CVE-2026-81014

What the bug is

sk_store() and kek_store() strip a trailing newline from the sysfs write before allocating the key buffer: length = count; if (buf[length - 1] == '\n') length--; bioscfg_drv.spm_data.signing_key = kmemdup(buf, length, GFP_KERNEL); but then pass the original "count" (not "length") as the copy size to hp_wmi_perform_query(), which memcpy()s that many bytes out of the "length"-sized allocation, reading one byte past it whenever the write ends in a newline, the normal case for a shell "echo" into sysfs. KASAN confirms this directly: BUG: KASAN: slab-out-of-bounds in hp_wmi_perform_query+0x1e9/0x460 [hp_bioscfg] Read of size 28 at addr ffff88813c8e2b80 by task python3/16022 ... sk_store+0xa7/0x240 [hp_bioscfg] kernfs_fop_write_iter+0x3e1/0x5d0 ... The buggy address is located 0 bytes inside of allocated 27-byte region [ffff88813c8e2b80, ffff88813c8e2b9b) Reproduced identically for kek_store, and at multiple write sizes (28, 57, 201 bytes), each time reading exactly one byte past a kmemdup() allocation one byte smaller than the write. Fix by passing "length" instead of "count" to hp_wmi_perform_query() in both functions.

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/platform/x86/hp/hp-bioscfg/spmobj-attributes.c

What this is

HP BIOSCFG DRIVERMAINTAINERS section matched on drivers/platform/x86/hp/hp-bioscfg/ · platform-driver-x86@vger.kernel.org · Maintained

Kernel module

hp_bioscfg

Check it on the machine

grep -wE 'CONFIG_HP_BIOSCFG|CONFIG_X86|CONFIG_X86_PLATFORM_DRIVERS_HP' /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 hp_bioscfg

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. The build rule could not be established for 1 release, so nothing is claimed about those.

• bookworm?
• 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, ppc64el/powerpc64le, ppc64el/powerpc64le-64k, 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, loong64/loong64, ppc64el/powerpc64le, ppc64el/powerpc64le-64k, 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, ppc64el/powerpc64le, ppc64el/powerpc64le-64k

?

not established - no Makefile entry for the affected file

M

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

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.

Build switches

CONFIG_HP_BIOSCFG, CONFIG_X86, CONFIG_X86_PLATFORM_DRIVERS_HP

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

2026-09-11 (37 days ago)source

CVSS

no vector published, unrated

Attack vector

not published

EPSS

0.17%, higher than 5.7% of all CVEssource

CISA KEV

not listedthe KEV catalogue

Debian urgency

unimportantsource

Subsystem

drivers/platform

Upstream fixes

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

Introduced	Fixed in	Commit
6.6	6.6.157	81db79fed115
6.6	6.12.109	4c6374dcb270
6.6	6.18.50	7cd8fe01aba3
6.6	7.2.4	67b60703d7d8
6.6	7.3	a7508c7959ff

Debian advisories