CVE-2026-93159

What the bug is

The nonblocking RNG path allocates a work_data structure to track the state of an in-flight asynchronous I2C request. This pointer is stored in rng->priv and later consumed by the read path once the transaction completes. If the underlying I2C transfer fails, the completion callback is invoked with a non-zero status. In this case, the allocated work_data is not usable for producing RNG output and must not remain associated with the hwrng state. Previously, the failure path only logged a warning but left the pointer state uncleared, which can result in subsequent read attempts observing stale state and interpreting it as valid completion data. Fix this by freeing the pending work_data. The I2C transaction reports an error. This ensures that failed requests do not leave residual state behind that could be interpreted as valid RNG data on later reads. Clearing rng->priv is done at the subsequent call to nonblocking read.

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/crypto/atmel-sha204a.c

What this is

MICROCHIP ATSHA204A DRIVERMAINTAINERS section matched on drivers/crypto/atmel-sha204a.c · linux-crypto@vger.kernel.org · Maintained

Kernel module

none to look for. The file would have gone into atmel_sha204a, and Debian does not compile it into that module, so finding atmel_sha204a in lsmod would say nothing about this CVE.

Check it on the machine

grep -wE 'CONFIG_CRYPTO|CONFIG_CRYPTO_DEV_ATMEL_SHA204A' /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 switches

CONFIG_CRYPTO, CONFIG_CRYPTO_DEV_ATMEL_SHA204A

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

0.22%, higher than 11.6% of all CVEssource

CISA KEV

not listedthe KEV catalogue

Debian urgency

not yet assignedsource

Subsystem

drivers/crypto

Upstream fixes

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

Introduced	Fixed in	Commit
5.3	5.10.270	a430b5b6d2dd
5.3	5.15.221	4e76d85e505b
5.3	6.1.188	bcac9052e194
5.3	6.6.157	28cc17925234
5.3	6.12.110	0d6db386133d
5.3	6.18.52	f4d347fb1309
5.3	7.2.6	94abda77b57a
5.3	7.3	72bbf11ba14b

Debian advisories