data built 2026-10-19T13:16:53Z

Look up another CVE · open CVE-2026-98387 in the interactive tracker

CVE-2026-98387

s390/crypto: Fix skcipher_walk return code handling in aes_s390

EPSS 0.2%

Published 2026-10-14 (4 days ago) by the Linux kernel CNA. Subsystem arch/s390. Debian urgency: not yet assigned.

What to do, per Debian release

Debian's own status for CVE-2026-98387 in every release this site tracks, and what each one means in practice. Every status below is the one the Debian Security Team publishes for this CVE. source

ReleaseStatus VersionWhat this means
Debian 12bookwormvulnerable6.1.190-1No fix published anywhere yet, neither in Debian nor upstream for the series bookworm tracks. Watch the Debian tracker page for this CVE. Advisories for bookworm have historically landed a median of 23 days after publication.
Debian 13trixiefixed6.12.111-1Update the kernel and reboot. Fixed in 6.12.111-1. A running kernel keeps the old code until the machine restarts.
Debian 14forkyfixed7.2.7-1Update the kernel and reboot. Fixed in 7.2.7-1. A running kernel keeps the old code until the machine restarts.
Debian unstablesidfixed7.2.7-1Update the kernel and reboot. Fixed in 7.2.7-1. A running kernel keeps the old code until the machine restarts.

The vulnerability

What the bug is

The return codes from skcipher_walk_virt() were not properly checked before entering the processing loops in ecb_aes_crypt() and ctr_aes_crypt(). If skcipher_walk_virt() fails, the walk structure may be in an undefined state, and attempting to process data could lead to incorrect behavior or accessing uninitialized memory. Add proper return code checking to ensure correct handling of the walk initialization and walk advance and eventually return to the caller with that return code.

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.

arch/s390/crypto/aes_s390.c

What this is
S390 CRYPTO MODULES, PRNG DRIVER, ARCH RANDOMMAINTAINERS section matched on arch/s390/crypto/ · linux-crypto@vger.kernel.org · Supported
Kernel module
aes_s390

Check it on the machine

grep -w CONFIG_CRYPTO_AES_S390 /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 aes_s390

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 does not build this code in 1 release. It does build it in 3 releases, so the answer depends on which release the machine runs.

  • bookwormn
  • trixieMnot built on amd64/amd64, amd64/cloud-amd64, amd64/rt/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
  • forky, sidMnot built on amd64/amd64, amd64/cloud-amd64, amd64/rt-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
n
not enabled on any flavour - this release does not build the code
M
a module where it is built at all; some flavours do not build it
Build switch
CONFIG_CRYPTO_AES_S390

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
2026-10-14 (4 days ago)source
CVSS
no vector published, unrated
Attack vector
not published
EPSS
0.21%, higher than 10.4% of all CVEssource
CISA KEV
not listedthe KEV catalogue
Debian urgency
not yet assignedsource
Subsystem
arch/s390

Upstream fixes

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

IntroducedFixed inCommit
5.56.12.11189b58645646d
5.56.18.5335c3f9756930
5.57.2.7aea3e1588f08
5.57.315fa028589c3

Why the CNA scored it this way

The kernel CNA published no CVSS vector and no reasoning for CVE-2026-98387, which is why it is shown as unrated rather than given an invented score. 6,405 of the 20,413 CVEs here carry reasoning; this is not one of them.