Improper access control in Linux kernel - CVE-2026-89984

 

Improper access control in Linux kernel - CVE-2026-89984

Published: September 16, 2026


Vulnerability identifier: #VU150302
CSH Severity: Low
CVSS v4: 4.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-89984
CWE-ID: CWE-284
Exploitation vector: Local access
Exploit availability: No public exploit available

Vulnerability details

The vulnerability allows a local user to disclose kernel addresses.

The vulnerability exists due to improper privilege-level validation in the intel_pmu_lbr_filter() LBR stack filtering function when filtering sampled LBR entries for user-only branch stacks. A local user can request a user-only branch stack through perf to disclose kernel addresses.

The issue affects systems where architectural LBR lacks CPL filtering support.


Affected software

Linux kernel
Debian Linux
SUSE Linux Enterprise Server for SAP Applications 15
SUSE Linux Enterprise Server 15
SUSE Linux Enterprise Desktop 15
SUSE Linux Enterprise High Availability Extension 15
SUSE Linux Enterprise Real Time 15
SUSE Linux Enterprise Workstation Extension 15
Basesystem Module
SUSE Real Time Module
SUSE Linux Enterprise Live Patching
Public Cloud Module
Legacy Module
Development Tools Module
Ubuntu
linux (Ubuntu package)
linux-kvm (Ubuntu package)
linux-aws (Ubuntu package)
linux-gcp (Ubuntu package)
linux-azure (Ubuntu package)
linux-oracle (Ubuntu package)
linux-lowlatency (Ubuntu package)
linux-gke (Ubuntu package)
linux-aws-5.15 (Ubuntu package)
linux-lowlatency-hwe-5.15 (Ubuntu package)
linux-hwe-5.15 (Ubuntu package)
linux-fips (Ubuntu package)
linux-azure-5.15 (Ubuntu package)
linux-nvidia-tegra (Ubuntu package)
linux-ibm-5.15 (Ubuntu package)
linux-azure-fde-5.15 (Ubuntu package)
linux-intel-iotg (Ubuntu package)
linux-realtime (Ubuntu package)
linux-gkeop (Ubuntu package)
linux-nvidia (Ubuntu package)
linux-nvidia-tegra-igx (Ubuntu package)
linux-ibm (Ubuntu package)
linux-intel-iotg-5.15 (Ubuntu package)
linux-oracle-5.15 (Ubuntu package)
linux-gcp-5.15 (Ubuntu package)
linux-nvidia-tegra-5.15 (Ubuntu package)
linux-azure-fde (Ubuntu package)
linux-intel-iot-realtime (Ubuntu package)
linux-gcp-fips (Ubuntu package)
linux-aws-fips (Ubuntu package)
linux-azure-fips (Ubuntu package)
linux-hwe-7.0 (Ubuntu package)
linux-oem-7.0 (Ubuntu package)
kernel-livepatch-6_4_0-150700_7_78-rt-debuginfo
kernel-livepatch-6_4_0-150700_7_78-rt
kernel-livepatch-SLE15-SP7-RT_Update_21-debugsource
kernel-livepatch-6_4_0-150700_53_84-default-debuginfo
kernel-livepatch-SLE15-SP7_Update_22-debugsource
kernel-livepatch-6_4_0-150700_53_84-default
kernel-rt
ocfs2-kmp-rt-debuginfo
cluster-md-kmp-rt-debuginfo
kernel-rt-debuginfo
kernel-rt-devel-debuginfo
kernel-rt-devel
kernel-syms-rt
kernel-rt-debugsource
cluster-md-kmp-rt
dlm-kmp-rt-debuginfo
gfs2-kmp-rt
gfs2-kmp-rt-debuginfo
ocfs2-kmp-rt
dlm-kmp-rt
kernel-devel-rt
kernel-source-rt
kernel-default-livepatch-devel
kernel-default-livepatch
cluster-md-kmp-default-debuginfo
kernel-azure
kernel-azure-debugsource
kernel-azure-devel
kernel-azure-debuginfo
kernel-azure-devel-debuginfo
kernel-default-extra
kernel-default-extra-debuginfo
kernel-macros
reiserfs-kmp-default-debuginfo
ocfs2-kmp-default
gfs2-kmp-default
dlm-kmp-default
gfs2-kmp-default-debuginfo
cluster-md-kmp-default
kernel-default-debugsource
dlm-kmp-default-debuginfo
kernel-default-debuginfo
ocfs2-kmp-default-debuginfo
kernel-default
kernel-default-devel
kernel-default-devel-debuginfo
kernel-devel
kernel-zfcpdump
kernel-zfcpdump-debugsource
kernel-zfcpdump-debuginfo
kernel-64kb
kernel-64kb-debuginfo
kernel-64kb-devel-debuginfo
kernel-64kb-debugsource
kernel-64kb-devel
kernel-docs
kernel-syms
kernel-obs-build
kernel-obs-build-debugsource
kernel-source
reiserfs-kmp-default
kernel-default-base
linux (Debian package)

How to mitigate CVE-2026-89984

Install security update from vendor's repository.

linux (Ubuntu package) - addressed in versions 5.15.0-202.212, 7.0.0-42.42
linux-kvm (Ubuntu package) - update to 5.15.0-1111.116
linux-aws (Ubuntu package) - addressed in versions 5.15.0-1119.126, 7.0.0-1016.17
linux-gcp (Ubuntu package) - addressed in versions 5.15.0-1120.130, 7.0.0-1016.18
linux-azure (Ubuntu package) - update to 5.15.0-1125.134
linux-oracle (Ubuntu package) - addressed in versions 5.15.0-1116.122, 7.0.0-1015.16
linux-lowlatency (Ubuntu package) - update to 5.15.0-197.207
linux-gke (Ubuntu package) - update to 5.15.0-1115.121
linux-aws-5.15 (Ubuntu package) - update to 5.15.0-1119.126~20.04.1
linux-lowlatency-hwe-5.15 (Ubuntu package) - update to 5.15.0-197.207~20.04.1
linux-hwe-5.15 (Ubuntu package) - update to 5.15.0-202.212~20.04.1
linux-fips (Ubuntu package) - update to 5.15.0-202.212+fips1
linux-azure-5.15 (Ubuntu package) - update to 5.15.0-1125.134~20.04.1
linux-nvidia-tegra (Ubuntu package) - update to 5.15.0-1070.72
linux-ibm-5.15 (Ubuntu package) - update to 5.15.0-1113.117~20.04.1
linux-azure-fde-5.15 (Ubuntu package) - update to 5.15.0-1124.133~20.04.1
linux-intel-iotg (Ubuntu package) - update to 5.15.0-1114.120
linux-realtime (Ubuntu package) - update to 5.15.0-1118.127
linux-gkeop (Ubuntu package) - update to 5.15.0-1102.110
linux-nvidia (Ubuntu package) - update to 5.15.0-1114.115
linux-nvidia-tegra-igx (Ubuntu package) - update to 5.15.0-1059.59
linux-ibm (Ubuntu package) - addressed in versions 5.15.0-1113.117, 7.0.0-1017.17
linux-intel-iotg-5.15 (Ubuntu package) - update to 5.15.0-1114.120~20.04.1
linux-oracle-5.15 (Ubuntu package) - update to 5.15.0-1116.122~20.04.1
linux-gcp-5.15 (Ubuntu package) - update to 5.15.0-1120.130~20.04.1
linux-nvidia-tegra-5.15 (Ubuntu package) - update to 5.15.0-1070.72~20.04.1
linux-azure-fde (Ubuntu package) - update to 5.15.0-1124.133
linux-intel-iot-realtime (Ubuntu package) - update to 5.15.0-1111.115
linux-gcp-fips (Ubuntu package) - update to 5.15.0-1120.130+fips1
linux-aws-fips (Ubuntu package) - update to 5.15.0-1119.126+fips1
linux-azure-fips (Ubuntu package) - update to 5.15.0-1125.134+fips1
linux-hwe-7.0 (Ubuntu package) - update to 7.0.0-42.42~24.04.1
linux-oem-7.0 (Ubuntu package) - update to 7.0.0-1017.17
kernel-livepatch-6_4_0-150700_7_78-rt-debuginfo - update to 1-150700.1.3.1
kernel-livepatch-6_4_0-150700_7_78-rt - update to 1-150700.1.3.1
kernel-livepatch-SLE15-SP7-RT_Update_21-debugsource - update to 1-150700.1.3.1
kernel-livepatch-6_4_0-150700_53_84-default-debuginfo - update to 1-150700.15.3.1
kernel-livepatch-SLE15-SP7_Update_22-debugsource - update to 1-150700.15.3.1
kernel-livepatch-6_4_0-150700_53_84-default - update to 1-150700.15.3.1
kernel-rt - update to 6.4.0-150700.7.78.1
ocfs2-kmp-rt-debuginfo - update to 6.4.0-150700.7.78.1
cluster-md-kmp-rt-debuginfo - update to 6.4.0-150700.7.78.1
kernel-rt-debuginfo - update to 6.4.0-150700.7.78.1
kernel-rt-devel-debuginfo - update to 6.4.0-150700.7.78.1
kernel-rt-devel - update to 6.4.0-150700.7.78.1
kernel-syms-rt - update to 6.4.0-150700.7.78.1
kernel-rt-debugsource - update to 6.4.0-150700.7.78.1
cluster-md-kmp-rt - update to 6.4.0-150700.7.78.1
dlm-kmp-rt-debuginfo - update to 6.4.0-150700.7.78.1
gfs2-kmp-rt - update to 6.4.0-150700.7.78.1
gfs2-kmp-rt-debuginfo - update to 6.4.0-150700.7.78.1
ocfs2-kmp-rt - update to 6.4.0-150700.7.78.1
dlm-kmp-rt - update to 6.4.0-150700.7.78.1
kernel-devel-rt - update to 6.4.0-150700.7.78.1
kernel-source-rt - update to 6.4.0-150700.7.78.1
kernel-default-livepatch-devel - update to 6.4.0-150700.53.84.1
kernel-default-livepatch - update to 6.4.0-150700.53.84.1
cluster-md-kmp-default-debuginfo - update to 6.4.0-150700.53.84.1
kernel-azure - update to 6.4.0-150700.53.84.1
kernel-azure-debugsource - update to 6.4.0-150700.53.84.1
kernel-azure-devel - update to 6.4.0-150700.53.84.1
kernel-azure-debuginfo - update to 6.4.0-150700.53.84.1
kernel-azure-devel-debuginfo - update to 6.4.0-150700.53.84.1
kernel-default-extra - update to 6.4.0-150700.53.84.1
kernel-default-extra-debuginfo - update to 6.4.0-150700.53.84.1
kernel-macros - update to 6.4.0-150700.53.84.1
reiserfs-kmp-default-debuginfo - update to 6.4.0-150700.53.84.1
ocfs2-kmp-default - update to 6.4.0-150700.53.84.1
gfs2-kmp-default - update to 6.4.0-150700.53.84.1
dlm-kmp-default - update to 6.4.0-150700.53.84.1
gfs2-kmp-default-debuginfo - update to 6.4.0-150700.53.84.1
cluster-md-kmp-default - update to 6.4.0-150700.53.84.1
kernel-default-debugsource - update to 6.4.0-150700.53.84.1
dlm-kmp-default-debuginfo - update to 6.4.0-150700.53.84.1
kernel-default-debuginfo - update to 6.4.0-150700.53.84.1
ocfs2-kmp-default-debuginfo - update to 6.4.0-150700.53.84.1
kernel-default - update to 6.4.0-150700.53.84.1
kernel-default-devel - update to 6.4.0-150700.53.84.1
kernel-default-devel-debuginfo - update to 6.4.0-150700.53.84.1
kernel-devel - update to 6.4.0-150700.53.84.1
kernel-zfcpdump - update to 6.4.0-150700.53.84.1
kernel-zfcpdump-debugsource - update to 6.4.0-150700.53.84.1
kernel-zfcpdump-debuginfo - update to 6.4.0-150700.53.84.1
kernel-64kb - update to 6.4.0-150700.53.84.1
kernel-64kb-debuginfo - update to 6.4.0-150700.53.84.1
kernel-64kb-devel-debuginfo - update to 6.4.0-150700.53.84.1
kernel-64kb-debugsource - update to 6.4.0-150700.53.84.1
kernel-64kb-devel - update to 6.4.0-150700.53.84.1
kernel-docs - update to 6.4.0-150700.53.84.1
kernel-syms - update to 6.4.0-150700.53.84.1
kernel-obs-build - update to 6.4.0-150700.53.84.1
kernel-obs-build-debugsource - update to 6.4.0-150700.53.84.1
kernel-source - update to 6.4.0-150700.53.84.1
reiserfs-kmp-default - update to 6.4.0-150700.53.84.1
kernel-default-base - update to 6.4.0-150700.53.84.1.150700.17.47.1
linux (Debian package) - update to 6.12.111-1

External References

Related Security Bulletins