Upstream information

CVE-2026-43073 at MITRE

Description

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

x86-64: rename misleadingly named '__copy_user_nocache()' function

This function was a masterclass in bad naming, for various historical
reasons.

It claimed to be a non-cached user copy. It is literally _neither_ of
those things. It's a specialty memory copy routine that uses
non-temporal stores for the destination (but not the source), and that
does exception handling for both source and destination accesses.

Also note that while it works for unaligned targets, any unaligned parts
(whether at beginning or end) will not use non-temporal stores, since
only words and quadwords can be non-temporal on x86.

The exception handling means that it _can_ be used for user space
accesses, but not on its own - it needs all the normal "start user space
access" logic around it.

But typically the user space access would be the source, not the
non-temporal destination. That was the original intention of this,
where the destination was some fragile persistent memory target that
needed non-temporal stores in order to catch machine check exceptions
synchronously and deal with them gracefully.

Thus that non-descriptive name: one use case was to copy from user space
into a non-cached kernel buffer. However, the existing users are a mix
of that intended use-case, and a couple of random drivers that just did
this as a performance tweak.

Some of those random drivers then actively misused the user copying
version (with STAC/CLAC and all) to do kernel copies without ever even
caring about the exception handling, _just_ for the non-temporal
destination.

Rename it as a first small step to actually make it halfway sane, and
change the prototype to be more normal: it doesn't take a user pointer
unless the caller has done the proper conversion, and the argument size
is the full size_t (it still won't actually copy more than 4GB in one
go, but there's also no reason to silently truncate the size argument in
the caller).

Finally, use this now sanely named function in the NTB code, which
mis-used a user copy version (with STAC/CLAC and all) of this interface
despite it not actually being a user copy at all.

SUSE information

Overall state of this security issue: Pending

This issue is currently rated as having moderate severity.

CVSS v3 Scores
CVSS detail SUSE
Base Score 6.3
Vector CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N
Attack Vector Local
Attack Complexity High
Privileges Required Low
User Interaction None
Scope Unchanged
Confidentiality Impact High
Integrity Impact High
Availability Impact None
CVSSv3 Version 3.1
CVSS v4 Scores
CVSS detail SUSE
Base Score 7.2
Vector CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
Attack Vector Local
Attack Complexity Low
Attack Requirements Present
Privileges Required Low
User Interaction None
Vulnerable System Confidentiality Impact High
Vulnerable System Integrity Impact High
Vulnerable System Availability Impact None
Subsequent System Confidentiality Impact None
Subsequent System Integrity Impact None
Subsequent System Availability Impact None
CVSSv4 Version 4.0

Note from the SUSE Security Team on the kernel-default package

SUSE will no longer fix all CVEs in the Linux Kernel anymore, but declare some bug classes as won't fix. Please refer to TID 21496 for more details.

SUSE Bugzilla entry: 1264454 [NEW]

No SUSE Security Announcements cross referenced.


Status of this issue by product and package

Please note that this evaluation state might be work in progress, incomplete or outdated. Also information for service packs in the LTSS phase is only included for issues meeting the LTSS criteria. If in doubt, feel free to contact us for clarification. The updates are grouped by state of their lifecycle. SUSE product lifecycles are documented on the lifecycle page.

Product(s) Source package State
Products under general support and receiving all security fixes.
SUSE Linux Enterprise Desktop 15 SP7 kernel-default Affected
SUSE Linux Enterprise Desktop 15 SP7 kernel-source Affected
SUSE Linux Enterprise High Availability Extension 15 SP7 kernel-default Affected
SUSE Linux Enterprise High Availability Extension 15 SP7 kernel-source Affected
SUSE Linux Enterprise High Performance Computing 15 SP7 kernel-default Affected
SUSE Linux Enterprise High Performance Computing 15 SP7 kernel-source Affected
SUSE Linux Enterprise Live Patching 15 SP7 kernel-default Affected
SUSE Linux Enterprise Live Patching 15 SP7 kernel-source Affected
SUSE Linux Enterprise Micro 5.3 kernel-default Affected
SUSE Linux Enterprise Micro 5.3 kernel-rt Affected
SUSE Linux Enterprise Micro 5.3 kernel-source Affected
SUSE Linux Enterprise Micro 5.3 kernel-source-rt Affected
SUSE Linux Enterprise Micro 5.4 kernel-default Affected
SUSE Linux Enterprise Micro 5.4 kernel-rt Affected
SUSE Linux Enterprise Micro 5.4 kernel-source Affected
SUSE Linux Enterprise Micro 5.4 kernel-source-rt Affected
SUSE Linux Enterprise Micro 5.5 kernel-default Affected
SUSE Linux Enterprise Micro 5.5 kernel-source Affected
SUSE Linux Enterprise Micro 5.5 kernel-source-rt Affected
SUSE Linux Enterprise Module for Basesystem 15 SP7 kernel-default Affected
SUSE Linux Enterprise Module for Basesystem 15 SP7 kernel-source Affected
SUSE Linux Enterprise Module for Development Tools 15 SP7 kernel-default Affected
SUSE Linux Enterprise Module for Development Tools 15 SP7 kernel-source Affected
SUSE Linux Enterprise Module for Legacy 15 SP7 kernel-default Affected
SUSE Linux Enterprise Module for Legacy 15 SP7 kernel-source Affected
SUSE Linux Enterprise Module for Public Cloud 15 SP7 kernel-default Affected
SUSE Linux Enterprise Module for Public Cloud 15 SP7 kernel-source Affected
SUSE Linux Enterprise Real Time 15 SP7 kernel-source-rt Affected
SUSE Linux Enterprise Server 15 SP7 kernel-default Affected
SUSE Linux Enterprise Server 15 SP7 kernel-source Affected
SUSE Linux Enterprise Server 16.0 kernel-default Affected
SUSE Linux Enterprise Server 16.0 kernel-source Affected
SUSE Linux Enterprise Server 16.1 kernel-source Affected
SUSE Linux Enterprise Server for SAP Applications 15 SP7 kernel-default Affected
SUSE Linux Enterprise Server for SAP Applications 15 SP7 kernel-source Affected
SUSE Linux Enterprise Server for SAP applications 16.0 kernel-default Affected
SUSE Linux Enterprise Server for SAP applications 16.0 kernel-source Affected
SUSE Linux Enterprise Server for SAP applications 16.1 kernel-source Affected
SUSE Linux Enterprise Workstation Extension 15 SP7 kernel-default Affected
SUSE Linux Enterprise Workstation Extension 15 SP7 kernel-source Affected
SUSE Linux Micro 6.0 kernel-default Affected
SUSE Linux Micro 6.0 kernel-source Affected
SUSE Linux Micro 6.0 kernel-source-rt Affected
SUSE Linux Micro 6.1 kernel-default Affected
SUSE Linux Micro 6.1 kernel-source Affected
SUSE Linux Micro 6.1 kernel-source-rt Affected
SUSE Linux Micro 6.2 kernel-default Affected
SUSE Linux Micro 6.2 kernel-source Affected
SUSE Real Time Module 15 SP7 kernel-source-rt Affected
Products under Long Term Service Pack support and receiving important and critical security fixes.
SUSE Linux Enterprise High Performance Computing 15 SP4 kernel-source Affected
SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS kernel-default Affected
SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS kernel-source Affected
SUSE Linux Enterprise High Performance Computing 15 SP5 kernel-source Affected
SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS kernel-default Affected
SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS kernel-source Affected
SUSE Linux Enterprise Live Patching 12 SP5 kernel-default Affected
SUSE Linux Enterprise Live Patching 12 SP5 kernel-source Affected
SUSE Linux Enterprise Live Patching 15 SP4 kernel-default Affected
SUSE Linux Enterprise Live Patching 15 SP4 kernel-source Affected
SUSE Linux Enterprise Live Patching 15 SP5 kernel-default Affected
SUSE Linux Enterprise Live Patching 15 SP5 kernel-source Affected
SUSE Linux Enterprise Module for Basesystem 15 SP4 kernel-source Affected
SUSE Linux Enterprise Module for Basesystem 15 SP5 kernel-source Affected
SUSE Linux Enterprise Module for Basesystem 15 SP6 kernel-source Affected
SUSE Linux Enterprise Module for Development Tools 15 SP4 kernel-source Affected
SUSE Linux Enterprise Module for Development Tools 15 SP5 kernel-source Affected
SUSE Linux Enterprise Module for Development Tools 15 SP6 kernel-source Affected
SUSE Linux Enterprise Server 11 SP4 LTSS EXTREME CORE kernel-default Affected
SUSE Linux Enterprise Server 11 SP4 LTSS EXTREME CORE kernel-source Affected
SUSE Linux Enterprise Server 12 SP5 kernel-source Affected
SUSE Linux Enterprise Server 12 SP5-LTSS kernel-default Affected
SUSE Linux Enterprise Server 12 SP5-LTSS kernel-source Affected
SUSE Linux Enterprise Server 12 SP5-LTSS Extended Security kernel-default Affected
SUSE Linux Enterprise Server 12 SP5-LTSS Extended Security kernel-source Affected
SUSE Linux Enterprise Server 15 SP4 kernel-source Affected
SUSE Linux Enterprise Server 15 SP4-LTSS kernel-default Affected
SUSE Linux Enterprise Server 15 SP4-LTSS kernel-source Affected
SUSE Linux Enterprise Server 15 SP5 kernel-source Affected
SUSE Linux Enterprise Server 15 SP5-LTSS kernel-default Affected
SUSE Linux Enterprise Server 15 SP5-LTSS kernel-source Affected
SUSE Linux Enterprise Server 15 SP6 kernel-source Affected
SUSE Linux Enterprise Server 15 SP6-LTSS kernel-default Affected
SUSE Linux Enterprise Server 15 SP6-LTSS kernel-source Affected
SUSE Linux Enterprise Server LTSS Extended Security 12 SP5 kernel-source Affected
SUSE Linux Enterprise Server for SAP Applications 15 SP6 kernel-default Affected
SUSE Linux Enterprise Server for SAP Applications 15 SP6 kernel-source Affected
SUSE Manager Proxy 4.3 kernel-source Affected
SUSE Manager Proxy LTS 4.3 kernel-source Affected
SUSE Manager Retail Branch Server 4.3 kernel-source Affected
SUSE Manager Retail Branch Server LTS 4.3 kernel-source Affected
SUSE Manager Server 4.3 kernel-source Affected
SUSE Manager Server LTS 4.3 kernel-source Affected
Products past their end of life and not receiving proactive updates anymore.
SUSE CaaS Platform 4.0 kernel-source Affected
SUSE Enterprise Storage 6 kernel-source Affected
SUSE Enterprise Storage 7 kernel-source Affected
SUSE Enterprise Storage 7.1 kernel-source Affected
SUSE Linux Enterprise Desktop 11 SP4 kernel-source Affected
SUSE Linux Enterprise Desktop 12 SP4 kernel-source Affected
SUSE Linux Enterprise Desktop 15 SP1 kernel-source Affected
SUSE Linux Enterprise Desktop 15 SP2 kernel-source Affected
SUSE Linux Enterprise Desktop 15 SP3 kernel-source Affected
SUSE Linux Enterprise Desktop 15 SP4 kernel-source Affected
SUSE Linux Enterprise Desktop 15 SP5 kernel-source Affected
SUSE Linux Enterprise Desktop 15 SP6 kernel-source Affected
SUSE Linux Enterprise High Performance Computing 15 SP1 kernel-source Affected
SUSE Linux Enterprise High Performance Computing 15 SP1-ESPOS kernel-source Affected
SUSE Linux Enterprise High Performance Computing 15 SP1-LTSS kernel-source Affected
SUSE Linux Enterprise High Performance Computing 15 SP2 kernel-source Affected
SUSE Linux Enterprise High Performance Computing 15 SP2-ESPOS kernel-source Affected
SUSE Linux Enterprise High Performance Computing 15 SP2-LTSS kernel-source Affected
SUSE Linux Enterprise High Performance Computing 15 SP3 kernel-source Affected
SUSE Linux Enterprise High Performance Computing 15 SP3-ESPOS kernel-source Affected
SUSE Linux Enterprise High Performance Computing 15 SP3-LTSS kernel-source Affected
SUSE Linux Enterprise High Performance Computing 15 SP4-ESPOS kernel-source Affected
SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS kernel-source Affected
SUSE Linux Enterprise High Performance Computing 15 SP6 kernel-source Affected
SUSE Linux Enterprise Micro 5.0 kernel-default Affected
SUSE Linux Enterprise Micro 5.1 kernel-default Affected
SUSE Linux Enterprise Micro 5.2 kernel-default Affected
SUSE Linux Enterprise Micro 5.2 kernel-source Affected
SUSE Linux Enterprise Module for Basesystem 15 SP1 kernel-source Affected
SUSE Linux Enterprise Module for Basesystem 15 SP2 kernel-source Affected
SUSE Linux Enterprise Module for Basesystem 15 SP3 kernel-source Affected
SUSE Linux Enterprise Module for Development Tools 15 SP1 kernel-source Affected
SUSE Linux Enterprise Module for Development Tools 15 SP2 kernel-source Affected
SUSE Linux Enterprise Module for Development Tools 15 SP3 kernel-source Affected
SUSE Linux Enterprise Real Time 15 SP2 kernel-source Affected
SUSE Linux Enterprise Real Time 15 SP3 kernel-source Affected
SUSE Linux Enterprise Real Time 15 SP4 kernel-source Affected
SUSE Linux Enterprise Real Time 15 SP4 kernel-source-rt Affected
SUSE Linux Enterprise Real Time 15 SP5 kernel-source-rt Affected
SUSE Linux Enterprise Server 11 SP4 kernel-source Affected
SUSE Linux Enterprise Server 11 SP4-LTSS kernel-source Affected
SUSE Linux Enterprise Server 12 SP4 kernel-source Affected
SUSE Linux Enterprise Server 12 SP4-ESPOS kernel-source Affected
SUSE Linux Enterprise Server 12 SP4-LTSS kernel-default Affected
SUSE Linux Enterprise Server 12 SP4-LTSS kernel-source Affected
SUSE Linux Enterprise Server 15 SP1 kernel-source Affected
SUSE Linux Enterprise Server 15 SP1-BCL kernel-source Affected
SUSE Linux Enterprise Server 15 SP1-LTSS kernel-default Affected
SUSE Linux Enterprise Server 15 SP1-LTSS kernel-source Affected
SUSE Linux Enterprise Server 15 SP2 kernel-source Affected
SUSE Linux Enterprise Server 15 SP2-BCL kernel-source Affected
SUSE Linux Enterprise Server 15 SP2-LTSS kernel-default Affected
SUSE Linux Enterprise Server 15 SP2-LTSS kernel-source Affected
SUSE Linux Enterprise Server 15 SP3 kernel-source Affected
SUSE Linux Enterprise Server 15 SP3-BCL kernel-source Affected
SUSE Linux Enterprise Server 15 SP3-LTSS kernel-default Affected
SUSE Linux Enterprise Server 15 SP3-LTSS kernel-source Affected
SUSE Linux Enterprise Server for SAP Applications 12 SP4 kernel-source Affected
SUSE Linux Enterprise Server for SAP Applications 15 SP1 kernel-source Affected
SUSE Linux Enterprise Server for SAP Applications 15 SP2 kernel-source Affected
SUSE Linux Enterprise Server for SAP Applications 15 SP3 kernel-source Affected
SUSE Linux Enterprise Server for SAP Applications 15 SP4 kernel-default Affected
SUSE Linux Enterprise Server for SAP Applications 15 SP4 kernel-source Affected
SUSE Linux Enterprise Server for SAP Applications 15 SP5 kernel-default Affected
SUSE Linux Enterprise Server for SAP Applications 15 SP5 kernel-source Affected
SUSE Manager Proxy 4.0 kernel-source Affected
SUSE Manager Proxy 4.1 kernel-source Affected
SUSE Manager Proxy 4.2 kernel-source Affected
SUSE Manager Retail Branch Server 4.0 kernel-source Affected
SUSE Manager Retail Branch Server 4.1 kernel-source Affected
SUSE Manager Retail Branch Server 4.2 kernel-source Affected
SUSE Manager Server 4.0 kernel-source Affected
SUSE Manager Server 4.1 kernel-source Affected
SUSE Manager Server 4.2 kernel-source Affected
SUSE OpenStack Cloud 9 kernel-source Affected
SUSE OpenStack Cloud Crowbar 9 kernel-source Affected
SUSE Real Time Module 15 SP4 kernel-source-rt Affected
SUSE Real Time Module 15 SP5 kernel-source-rt Affected
openSUSE Leap 15.3 kernel-source Affected
openSUSE Leap 15.4 kernel-source Affected
openSUSE Leap 15.4 kernel-source-rt Affected
openSUSE Leap 15.5 kernel-source Affected
openSUSE Leap 15.5 kernel-source-rt Affected
openSUSE Leap 15.6 kernel-source Affected


SUSE Timeline for this CVE

CVE page created: Tue May 5 20:22:10 2026
CVE page last modified: Fri May 8 15:16:27 2026