high 7.8

CVE-2025-39788 json

scsi: ufs: exynos: Fix programming of HCI_UTRL_NEXUS_TYPE

published 2025-09-11 13 mo ago modified 2026-10-19 20 d ago also EUVD-2025-28925

cvss: 7.8; version 3.1, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 0.2%; EPSS 0.2% chance of exploitation in 30 days, percentile 6%
public exploits: 0; none known

In the Linux kernel, the following vulnerability has been resolved:

On Google gs101, the number of UTP transfer request slots (nutrs) is 32, and in this case the driver ends up programming the UTRL_NEXUS_TYPE incorrectly as 0.

This is because the left hand side of the shift is 1, which is of type int, i.e. 31 bits wide. Shifting by more than that width results in undefined behaviour.

Fix this by switching to the BIT() macro, which applies correct type casting as required. This ensures the correct value is written to UTRL_NEXUS_TYPE (0xffffffff on gs101), and it also fixes a UBSAN shift warning:

UBSAN: shift-out-of-bounds in drivers/ufs/host/ufs-exynos.c:1113:21 shift exponent 32 is too large for 32-bit type 'int'

For consistency, apply the same change to the nutmrs / UTMRL_NEXUS_TYPE write.

Patch / fix

fixed in 2 distros 4 links 7

Linux Linux 5.10.241, 5.15.190, 6.1.149, 6.6.103, 6.12.44, 6.16.4, 6.17
Siemens SIMATIC CN 4100 V5.0

debian ubuntu suse opensuse

linux Debian 12 6.1.153-1
linux Debian 13 6.12.48-1
linux Debian 14 6.16.5-1

debian advisories DEBIAN-CVE-2025-39788

linux Ubuntu 22.04 LTS 5.15.0-163.173
linux Ubuntu 24.04 LTS 6.8.0-100.100
linux-aws Ubuntu 22.04 LTS 5.15.0-1097.104
linux-aws Ubuntu 24.04 LTS 6.8.0-1046.49
linux-gcp Ubuntu 22.04 LTS 5.15.0-1097.106
linux-gcp Ubuntu 24.04 LTS 6.8.0-1047.50
linux-gke Ubuntu 22.04 LTS 5.15.0-1093.99
linux-gke Ubuntu 24.04 LTS 6.8.0-1043.48

ubuntu advisories UBUNTU-CVE-2025-39788

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

kernel-source Linux Micro 6.1, Linux Micro 6.0 6.4.0-38.1
kernel-default Linux Micro 6.1, Linux Micro 6.0 6.4.0-38.1
kernel-kvmsmall Linux Micro 6.1, Linux Micro 6.0 6.4.0-38.1
kernel-default-base Linux Micro 6.1, Linux Micro 6.0 6.4.0-38.1.21.15
kernel-rt Linux Micro 6.1, Linux Micro 6.0 6.4.0-39.1
kernel-source-rt Linux Micro 6.1, Linux Micro 6.0 6.4.0-39.1
kernel-rt Real Time Module 15 SP6, openSUSE Leap 15.6 6.4.0-150600.10.61.1
kernel-syms-rt Real Time Module 15 SP6, openSUSE Leap 15.6 6.4.0-150600.10.61.1

suse advisories SUSE-SU-2026:20473-1 SUSE-SU-2026:20496-1 SUSE-SU-2026:20039-1 SUSE-SU-2026:20059-1 SUSE-SU-2025:4521-1 SUSE-SU-2025:4517-1

kernel-rt openSUSE Leap 16.0 6.12.0-160000.6.1
dtb-aarch64 openSUSE Leap 16.0 6.12.0-160000.6.1
kernel-64kb openSUSE Leap 16.0 6.12.0-160000.6.1
kernel-syms openSUSE Leap 16.0 6.12.0-160000.6.1
kernel-obs-qa openSUSE Leap 16.0 6.12.0-160000.6.1
kernel-source openSUSE Leap 16.0 6.12.0-160000.6.1
kernel-default openSUSE Leap 16.0 6.12.0-160000.6.1
kernel-kvmsmall openSUSE Leap 16.0 6.12.0-160000.6.1

opensuse advisories openSUSE-SU-2025:20081-1

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2025-39788 updated 2026-11-07

kernel: scsi: ufs: exynos: Fix programming of HCI_UTRL_NEXUS_TYPE

Red Hat Enterprise Linux 6 perf, kernel, python-perf, kernel-kdump, kernel-firmware, kernel-bootwrapper, +1 more Red Hat Enterprise Linux 7 perf, kernel, bpftool, kernel-rt, python-perf, kernel-kdump, +8 more Red Hat Enterprise Linux 8 perf, kernel, bpftool, kernel-rt, kernel-core, kernel-tools, +29 more Red Hat Enterprise Linux 9 rv, perf, rtla, kernel, bpftool, libperf, +83 more Red Hat Enterprise Linux 10 kernel
not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

cisa ICSA-26-134-10 updated 2026-05-14 cvss 5.5

Siemens SIMATIC

Siemens SIMATIC CN 4100 < 5.0
affected: fixed in V5.0 support.industry.siemens.com

Facts from CISA's republication of the vendor's own advisory (CSAF); the linked advisory is the authoritative source. CISA notification · csaf

Exploit prediction

0.17% chance of exploitation in the next 30 days, higher than 6% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
NVD	3.1	7.8	CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Affected products

Linux Linux
Siemens SIMATIC CN 4100

Classification

Weakness

CWE-787 Out-of-bounds Write

Technology feeds

Linux kernel rss critical rss

References

Sources

CVE List CVE-2025-39788
NVD CVE-2025-39788

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary