CVE-2026-92480

What the bug is

The string descriptor length includes a two-byte header while the UTF-16 payload starts after it. utf16s_to_utf8s() expects a count of UTF-16 code units, not bytes. Passing the payload byte count can make it read beyond the descriptor buffer. Validate that the payload has an even byte count, pass a code-unit count to the converter, and allocate sufficient UTF-8 output space. The raw string buffer starts after the descriptor header but its size is bLength. Copying bLength bytes from that pointer can read beyond the response buffer. Allocate a zeroed bLength-sized buffer and copy only the UTF-16 payload. This preserves the raw buffer size consumed by the RPMB device-ID ABI while avoiding the overread.

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/ufs/core/ufshcd.c

What this is

UNIVERSAL FLASH STORAGE HOST CONTROLLER DRIVERMAINTAINERS section matched on drivers/ufs/core/ · linux-scsi@vger.kernel.org · Supported

Kernel module

ufshcd_core

Check it on the machine

grep -w CONFIG_SCSI_UFSHCD /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 ufshcd_core

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, sidMnot built on amd64/cloud-amd64, arm64/cloud-arm64

M

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

Build switch

CONFIG_SCSI_UFSHCD

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

0.21%, higher than 10.0% of all CVEssource

CISA KEV

not listedthe KEV catalogue

Debian urgency

not yet assignedsource

Subsystem

drivers/ufs

Upstream fixes

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

Introduced	Fixed in	Commit
5.4	6.18.57	f3480c59f4ce
5.4	7.2.6	66da25277256
5.4	7.3	d96e83d028d7