Upstream information

CVE-2026-89928 at MITRE

Description

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

KVM: x86/mmu: Consume the locked rmap value in the lockless rmap walk

__kvm_rmap_lock() deliberately elides the rmap lock when it observes an
empty rmap. In that case kvm_rmap_lock_readonly() also re-enables
preemption and returns zero, so the caller holds neither the rmap lock
nor a preemption reference. The elision documents the invariant it
relies on:

* Elide the lock if the rmap is empty, as lockless walkers (read-only
* mode) don't need to (and can't) walk an empty rmap, nor can they add
* entries to the rmap. I.e. the only paths that process empty rmaps
* do so while holding mmu_lock for write, and are mutually exclusive.

kvm_rmap_age_gfn_range() ignores the returned value and unconditionally
enters for_each_rmap_spte_lockless(). The iterator started with
rmap_get_first(), which re-reads rmap_head->val rather than using the
value returned by the lock. If a writer populates the rmap between the
lock's read and the iterator's re-read, the aging path walks the newly
installed rmap without holding its lock.

For a KVM_RMAP_MANY rmap this leaves the walker following a
pte_list_desc chain that it never locked. A writer holding mmu_lock for
write may free that chain (e.g. kvm_zap_all_rmap_sptes() on the recycle
path, or any rmap zap) via kmem_cache_free() while the walk is in
progress, giving a slab use-after-free. Nothing serialises the two: the
aging path runs without mmu_lock when CONFIG_KVM_MMU_LOCKLESS_AGING=y,
and the rmap lock that would otherwise exclude the writer was elided.
Because the empty path re-enables preemption, the interval between the
two reads can span an arbitrary scheduling delay.

Fix the class of bug by having the lockless walk consume the value
returned by the lock instead of re-reading the rmap. Split
rmap_get_first() into __rmap_get_first(), which starts an iterator from
an already-read rmap value, and make for_each_rmap_spte_lockless() take
that value and call __rmap_get_first() directly.
kvm_rmap_age_gfn_range() passes the value returned by
kvm_rmap_lock_readonly(): when the lock was elided the value is zero,
__rmap_get_first() returns NULL, and the walk is skipped. No lockless
walker re-reads the rmap, so the lock-elision invariant cannot be
violated, and no lock()-without-paired-unlock() path is added to the
aging code.

SUSE information

Overall state of this security issue: Resolved

This issue is currently rated as having moderate severity.

CVSS v3 Scores
CVSS detail CNA (NVD) Linux Kernel CNA SUSE
Base Score 8.8 8.8 5.8
Vector CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:H
Attack Vector Local Local Local
Attack Complexity Low Low High
Privileges Required Low Low Low
User Interaction None None None
Scope Changed Changed Unchanged
Confidentiality Impact High High Low
Integrity Impact High High Low
Availability Impact High High High
CVSSv3 Version 3.1 3.1 3.1
CVSS v4 Scores
CVSS detail SUSE
Base Score 5.8
Vector CVSS:4.0/AV:L/AC:H/AT:P/PR:L/UI:N/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N
Attack Vector Local
Attack Complexity High
Attack Requirements Present
Privileges Required Low
User Interaction None
Vulnerable System Confidentiality Impact Low
Vulnerable System Integrity Impact Low
Vulnerable System Availability Impact High
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: 1281355 [NEW]

No SUSE Security Announcements cross referenced.

List of released packages

Product(s) Fixed package version(s) References
openSUSE Tumbleweed
  • kernel-devel >= 7.2.7-1.1
  • kernel-macros >= 7.2.7-1.1
  • kernel-source >= 7.2.7-1.1
  • kernel-source-vanilla >= 7.2.7-1.1
Patchnames:
openSUSE-Tumbleweed-2026-11880


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 Not affected
SUSE Linux Enterprise Desktop 15 SP7 kernel-source Not affected
SUSE Linux Enterprise High Availability Extension 15 SP7 kernel-default Not affected
SUSE Linux Enterprise High Availability Extension 15 SP7 kernel-source Not affected
SUSE Linux Enterprise High Availability Extension 16.0 kernel-default Not affected
SUSE Linux Enterprise High Availability Extension 16.0 kernel-source Not affected
SUSE Linux Enterprise High Availability Extension 16.1 kernel-default Not affected
SUSE Linux Enterprise High Availability Extension 16.1 kernel-source Not affected
SUSE Linux Enterprise Micro 5.3 kernel-default Not affected
SUSE Linux Enterprise Micro 5.3 kernel-rt Not affected
SUSE Linux Enterprise Micro 5.3 kernel-source Not affected
SUSE Linux Enterprise Micro 5.3 kernel-source-rt Not affected
SUSE Linux Enterprise Micro 5.4 kernel-default Not affected
SUSE Linux Enterprise Micro 5.4 kernel-rt Not affected
SUSE Linux Enterprise Micro 5.4 kernel-source Not affected
SUSE Linux Enterprise Micro 5.4 kernel-source-rt Not affected
SUSE Linux Enterprise Micro 5.5 kernel-default Not affected
SUSE Linux Enterprise Micro 5.5 kernel-source Not affected
SUSE Linux Enterprise Micro 5.5 kernel-source-rt Not affected
SUSE Linux Enterprise Module for Basesystem 15 SP7 kernel-default Not affected
SUSE Linux Enterprise Module for Basesystem 15 SP7 kernel-source Not affected
SUSE Linux Enterprise Module for Development Tools 15 SP7 kernel-default Not affected
SUSE Linux Enterprise Module for Development Tools 15 SP7 kernel-source Not affected
SUSE Linux Enterprise Real Time 15 SP7 kernel-source-rt Not affected
SUSE Linux Enterprise Server 15 SP7 kernel-default Not affected
SUSE Linux Enterprise Server 15 SP7 kernel-source Not affected
SUSE Linux Enterprise Server 16.0 kernel-default Not affected
SUSE Linux Enterprise Server 16.0 kernel-source Not affected
SUSE Linux Enterprise Server 16.1 kernel-default Not affected
SUSE Linux Enterprise Server 16.1 kernel-source Not affected
SUSE Linux Enterprise Server for SAP Applications 15 SP7 kernel-default Not affected
SUSE Linux Enterprise Server for SAP Applications 15 SP7 kernel-source Not affected
SUSE Linux Enterprise Server for SAP applications 16.0 kernel-default Not affected
SUSE Linux Enterprise Server for SAP applications 16.0 kernel-source Not affected
SUSE Linux Enterprise Server for SAP applications 16.1 kernel-default Not affected
SUSE Linux Enterprise Server for SAP applications 16.1 kernel-source Not affected
SUSE Linux Micro 6.0 kernel-default Not affected
SUSE Linux Micro 6.0 kernel-source Not affected
SUSE Linux Micro 6.0 kernel-source-rt Not affected
SUSE Linux Micro 6.1 kernel-default Not affected
SUSE Linux Micro 6.1 kernel-source Not affected
SUSE Linux Micro 6.1 kernel-source-rt Not affected
SUSE Linux Micro 6.2 kernel-default Not affected
SUSE Linux Micro 6.2 kernel-source Not affected
SUSE Linux Micro Extras 6.0 kernel-default Not affected
SUSE Linux Micro Extras 6.0 kernel-source Not affected
SUSE Linux Micro Extras 6.0 kernel-source-rt Not affected
SUSE Linux Micro Extras 6.1 kernel-default Not affected
SUSE Linux Micro Extras 6.1 kernel-source Not affected
SUSE Real Time Module 15 SP7 kernel-source-rt Not affected
openSUSE Leap 16.0 kernel-source Not affected
Products under Long Term Service Pack support and receiving important and critical security fixes.
SUSE Linux Enterprise High Performance Computing 12 SP5 kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS kernel-default Not affected
SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP5 kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS kernel-default Not affected
SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS kernel-source Not affected
SUSE Linux Enterprise Module for Basesystem 15 SP4 kernel-source Not affected
SUSE Linux Enterprise Module for Basesystem 15 SP5 kernel-source Not affected
SUSE Linux Enterprise Module for Basesystem 15 SP6 kernel-source Not affected
SUSE Linux Enterprise Module for Development Tools 15 SP4 kernel-source Not affected
SUSE Linux Enterprise Module for Development Tools 15 SP5 kernel-source Not affected
SUSE Linux Enterprise Module for Development Tools 15 SP6 kernel-source Not affected
SUSE Linux Enterprise Server 11 SP4 LTSS EXTREME CORE kernel-default Not affected
SUSE Linux Enterprise Server 11 SP4 LTSS EXTREME CORE kernel-source Not affected
SUSE Linux Enterprise Server 12 SP5 kernel-source Not affected
SUSE Linux Enterprise Server 12 SP5-LTSS kernel-default Not affected
SUSE Linux Enterprise Server 12 SP5-LTSS kernel-source Not affected
SUSE Linux Enterprise Server 15 SP4 kernel-source Not affected
SUSE Linux Enterprise Server 15 SP4-LTSS kernel-default Not affected
SUSE Linux Enterprise Server 15 SP4-LTSS kernel-source Not affected
SUSE Linux Enterprise Server 15 SP5 kernel-source Not affected
SUSE Linux Enterprise Server 15 SP5-LTSS kernel-default Not affected
SUSE Linux Enterprise Server 15 SP5-LTSS kernel-source Not affected
SUSE Linux Enterprise Server 15 SP6 kernel-source Not affected
SUSE Linux Enterprise Server 15 SP6-LTSS kernel-default Not affected
SUSE Linux Enterprise Server 15 SP6-LTSS kernel-source Not affected
SUSE Linux Enterprise Server LTSS Extended Security 12 SP5 kernel-default Not affected
SUSE Linux Enterprise Server LTSS Extended Security 12 SP5 kernel-source Not affected
SUSE Linux Enterprise Server for SAP Applications 15 SP4 kernel-default Not affected
SUSE Linux Enterprise Server for SAP Applications 15 SP4 kernel-source Not affected
SUSE Linux Enterprise Server for SAP Applications 15 SP5 kernel-default Not affected
SUSE Linux Enterprise Server for SAP Applications 15 SP5 kernel-source Not affected
SUSE Linux Enterprise Server for SAP Applications 15 SP6 kernel-default Not affected
SUSE Linux Enterprise Server for SAP Applications 15 SP6 kernel-source Not affected
Products past their end of life and not receiving proactive updates anymore.
SUSE CaaS Platform 4.0 kernel-source Not affected
SUSE Enterprise Storage 6 kernel-source Not affected
SUSE Enterprise Storage 7 kernel-source Not affected
SUSE Enterprise Storage 7.1 kernel-source Not affected
SUSE Linux Enterprise Desktop 11 SP4 kernel-source Not affected
SUSE Linux Enterprise Desktop 15 SP1 kernel-source Not affected
SUSE Linux Enterprise Desktop 15 SP2 kernel-source Not affected
SUSE Linux Enterprise Desktop 15 SP3 kernel-source Not affected
SUSE Linux Enterprise Desktop 15 SP4 kernel-source Not affected
SUSE Linux Enterprise Desktop 15 SP5 kernel-source Not affected
SUSE Linux Enterprise Desktop 15 SP6 kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP1 kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP1-ESPOS kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP1-LTSS kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP2 kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP2-ESPOS kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP2-LTSS kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP3 kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP3-ESPOS kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP3-LTSS kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP4 kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP4-ESPOS kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS kernel-source Not affected
SUSE Linux Enterprise Micro 5.0 kernel-default Not affected
SUSE Linux Enterprise Micro 5.1 kernel-default Not affected
SUSE Linux Enterprise Micro 5.2 kernel-default Not affected
SUSE Linux Enterprise Micro 5.2 kernel-source Not affected
SUSE Linux Enterprise Module for Basesystem 15 SP1 kernel-source Not affected
SUSE Linux Enterprise Module for Basesystem 15 SP2 kernel-source Not affected
SUSE Linux Enterprise Module for Basesystem 15 SP3 kernel-source Not affected
SUSE Linux Enterprise Module for Development Tools 15 SP1 kernel-source Not affected
SUSE Linux Enterprise Module for Development Tools 15 SP2 kernel-source Not affected
SUSE Linux Enterprise Module for Development Tools 15 SP3 kernel-source Not affected
SUSE Linux Enterprise Real Time 15 SP2 kernel-source Not affected
SUSE Linux Enterprise Real Time 15 SP3 kernel-source Not affected
SUSE Linux Enterprise Real Time 15 SP4 kernel-source Not affected
SUSE Linux Enterprise Real Time 15 SP4 kernel-source-rt Not affected
SUSE Linux Enterprise Real Time 15 SP5 kernel-source-rt Not affected
SUSE Linux Enterprise Server 11 SP4 kernel-source Not affected
SUSE Linux Enterprise Server 11 SP4-LTSS kernel-source Not affected
SUSE Linux Enterprise Server 15 SP1 kernel-source Not affected
SUSE Linux Enterprise Server 15 SP1-BCL kernel-source Not affected
SUSE Linux Enterprise Server 15 SP1-LTSS kernel-default Not affected
SUSE Linux Enterprise Server 15 SP1-LTSS kernel-source Not affected
SUSE Linux Enterprise Server 15 SP2 kernel-source Not affected
SUSE Linux Enterprise Server 15 SP2-BCL kernel-source Not affected
SUSE Linux Enterprise Server 15 SP2-LTSS kernel-default Not affected
SUSE Linux Enterprise Server 15 SP2-LTSS kernel-source Not affected
SUSE Linux Enterprise Server 15 SP3 kernel-source Not affected
SUSE Linux Enterprise Server 15 SP3-BCL kernel-source Not affected
SUSE Linux Enterprise Server 15 SP3-LTSS kernel-default Not affected
SUSE Linux Enterprise Server 15 SP3-LTSS kernel-source Not affected
SUSE Linux Enterprise Server for SAP Applications 15 SP1 kernel-source Not affected
SUSE Linux Enterprise Server for SAP Applications 15 SP2 kernel-source Not affected
SUSE Linux Enterprise Server for SAP Applications 15 SP3 kernel-source Not affected
SUSE Manager Proxy 4.0 kernel-source Not affected
SUSE Manager Proxy 4.1 kernel-source Not affected
SUSE Manager Proxy 4.2 kernel-source Not affected
SUSE Manager Proxy 4.3 kernel-source Not affected
SUSE Manager Proxy LTS 4.3 kernel-source Not affected
SUSE Manager Retail Branch Server 4.0 kernel-source Not affected
SUSE Manager Retail Branch Server 4.1 kernel-source Not affected
SUSE Manager Retail Branch Server 4.2 kernel-source Not affected
SUSE Manager Retail Branch Server 4.3 kernel-source Not affected
SUSE Manager Retail Branch Server LTS 4.3 kernel-source Not affected
SUSE Manager Server 4.0 kernel-source Not affected
SUSE Manager Server 4.1 kernel-source Not affected
SUSE Manager Server 4.2 kernel-source Not affected
SUSE Manager Server 4.3 kernel-source Not affected
SUSE Manager Server LTS 4.3 kernel-source Not affected
SUSE Real Time Module 15 SP4 kernel-source-rt Not affected
SUSE Real Time Module 15 SP5 kernel-source-rt Not affected
openSUSE Leap 15.3 kernel-source Not affected
openSUSE Leap 15.4 kernel-source Not affected
openSUSE Leap 15.4 kernel-source-rt Not affected
openSUSE Leap 15.5 kernel-source Not affected
openSUSE Leap 15.5 kernel-source-rt Not affected
openSUSE Leap 15.6 kernel-source Not affected
Products at an unknown state of their lifecycle.
SUSE Linux Enterprise Server for NVIDIA 16.1 kernel-source Not affected


SUSE Timeline for this CVE

CVE page created: Thu Sep 17 16:09:05 2026
CVE page last modified: Thu Oct 1 18:49:23 2026