CVE-2026-93234

What the bug is

The GUD protocol returns TV mode names as fixed-size GUD_CONNECTOR_TV_MODE_NAME_LEN entries and requires each name to be NUL-terminated. gud_connector_add_tv_mode() currently passes each fixed-size entry directly to drm_mode_create_tv_properties_legacy(), which eventually reaches drm_property_add_enum() and strlen(). If a device returns an entry without a terminating NUL byte, strlen() reads past the end of the slot and can run beyond the allocated buffer, triggering an out-of-bounds read. Validate that each returned TV mode name contains a NUL terminator within its fixed-size slot before passing it to the DRM property code. If a malformed entry is found, reject the device response with -EIO. This fixes the out-of-bounds read without changing the handling of valid devices, and avoids silently truncating malformed protocol data.

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/gpu/drm/gud/gud_connector.c

What this is

DRM DRIVER FOR GENERIC USB DISPLAYMAINTAINERS section matched on drivers/gpu/drm/gud/ · Maintained

Kernel module

none to look for. The file would have gone into gud, and Debian does not compile it into that module, so finding gud in lsmod would say nothing about this CVE.

Check it on the machine

grep -w CONFIG_DRM_GUD /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.

Show whether Debian builds this, per release

Debian does not build this code. In 5 releases below, every kernel flavour Debian publishes has the switch off, so the vulnerable file is compiled into no kernel binary Debian ships.

• bookworm, trixie, forky, sid, bookworm · linux-6.12n

n

not enabled on any flavour - this release does not build the code

Build switch

CONFIG_DRM_GUD

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

2026-09-24 (24 days ago)source

CVSS

no vector published, unrated

Attack vector

not published

EPSS

0.21%, higher than 9.9% of all CVEssource

CISA KEV

not listedthe KEV catalogue

Debian urgency

not yet assignedsource

Subsystem

drivers/gpu

Upstream fixes

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

Introduced	Fixed in	Commit
5.13	5.15.221	676f1fb3632b
5.13	6.1.188	06fcaf21c18a
5.13	6.6.157	082e37888654
5.13	6.12.110	70cffc31a380
5.13	6.18.51	72a95df6bbc7
5.13	7.2.5	eab46d962980
5.13	7.3	da1ea35fea67

Debian advisories