CVE-2026-93053

What the bug is

help_init() builds letter_offsets[] by using the first byte of each function name as an index via `(start & 31) - 1`. If function_names are overridden from sysfs (root) with a name starting outside [a–z], the index underflows or exceeds the array, leading to OOB write. Function names can be overridden with the following commands as root: modprobe speakup_soft echo "0 _bad" > /sys/accessibility/speakup/i18n/function_names # then press Insert+2 on /dev/tty This fix checks the first letter in help_init(), and if it is not in the [a–z] range the function returns an error to the caller. Eventually this error is propagated to drivers/accessibility/speakup/main.c:2217, which causes a bleep sound.

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/accessibility/speakup/keyhelp.c

What this is

SPEAKUP CONSOLE SPEECH DRIVERMAINTAINERS section matched on drivers/accessibility/speakup/ · speakup@linux-speakup.org · Odd Fixes

Kernel module

speakup

Check it on the machine

grep -wE 'CONFIG_ACCESSIBILITY|CONFIG_SPEAKUP' /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 speakup

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.

• bookworm, trixie, forky, sid, bookworm · linux-6.12Mnot built on amd64/cloud-amd64, arm64/cloud-arm64

M

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

Build switches

CONFIG_ACCESSIBILITY, CONFIG_SPEAKUP

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

2026-09-17 (31 days ago)source

CVSS

no vector published, unrated

Attack vector

not published

EPSS

0.18%, higher than 6.8% of all CVEssource

CISA KEV

not listedthe KEV catalogue

Debian urgency

not yet assignedsource

Subsystem

drivers/accessibility

Upstream fixes

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

Introduced	Fixed in	Commit
2.6.37	5.10.270	fd339b9ef0ac
2.6.37	5.15.221	900cd6e5ef46
2.6.37	6.1.188	6b39969c724d
2.6.37	6.6.157	2e91ab73f9be
2.6.37	6.12.110	d7deb90c4cd0
2.6.37	6.18.52	5310334762c3
2.6.37	7.2.6	ca4489b3e546
2.6.37	7.3	6a19ad4d68c9

Debian advisories