Deadlock in Linux kernel - CVE-2026-46063

 

Deadlock in Linux kernel - CVE-2026-46063

Published: May 28, 2026


Vulnerability identifier: #VU132427
CSH Severity: Low
CVSS v4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-46063
CWE-ID: CWE-833
Exploitation vector: Local access
Exploit availability: No public exploit available

Vulnerability details

The vulnerability allows a local user to cause a denial of service.

The vulnerability exists due to improper locking in shadow stack signal frame handling during sigreturn when reading the shadow stack signal frame from userspace. A local user can trigger a page fault during sigreturn to cause a denial of service.

The issue can occur when a writer on another CPU is waiting on the mmap lock, leading to a deadlock in the fault handling path.


Affected software

Linux kernel
SUSE Linux Enterprise Server for SAP Applications 15
SUSE Linux Enterprise Server 15
SUSE Linux Enterprise Real Time 15
SUSE Linux Enterprise High Availability Extension 15
SUSE Linux Enterprise Desktop 15
SUSE Linux Enterprise Workstation Extension 15
SUSE Linux Micro Extras
SUSE Linux Micro
SUSE Linux Enterprise Live Patching
SUSE Real Time Module
Basesystem Module
Development Tools Module
Legacy Module
Public Cloud Module
Ubuntu
kernel-livepatch-6_4_0-150700_7_62-rt
kernel-livepatch-SLE15-SP7-RT_Update_17-debugsource
kernel-livepatch-6_4_0-150700_7_62-rt-debuginfo
kernel-livepatch-6_4_0-150700_53_66-default
kernel-livepatch-SLE15-SP7_Update_18-debugsource
kernel-livepatch-6_4_0-150700_53_66-default-debuginfo
kernel-kvmsmall-debuginfo
kernel-rt-devel
kernel-source
kernel-macros
kernel-devel
kernel-default-livepatch
kernel-default-debuginfo
kernel-default-debugsource
kernel-kvmsmall
kernel-default
kernel-rt-devel-debuginfo
kernel-rt-debugsource
kernel-rt
kernel-default-devel-debuginfo
kernel-kvmsmall-debugsource
kernel-rt-livepatch
kernel-rt-debuginfo
kernel-source-rt
kernel-devel-rt
kernel-64kb-debugsource
kernel-64kb-devel
kernel-obs-build
kernel-default-devel
kernel-obs-build-debugsource
kernel-syms
kernel-64kb
dlm-kmp-rt
gfs2-kmp-rt-debuginfo
gfs2-kmp-rt
ocfs2-kmp-rt-debuginfo
cluster-md-kmp-rt
kernel-syms-rt
cluster-md-kmp-rt-debuginfo
ocfs2-kmp-rt
dlm-kmp-rt-debuginfo
kernel-64kb-debuginfo
kernel-zfcpdump
kernel-zfcpdump-debugsource
kernel-zfcpdump-debuginfo
kernel-64kb-devel-debuginfo
kernel-azure-devel
kernel-default-livepatch-devel
kernel-azure
kernel-azure-devel-debuginfo
kernel-azure-debugsource
kernel-azure-debuginfo
kernel-default-extra
kernel-default-extra-debuginfo
reiserfs-kmp-default-debuginfo
reiserfs-kmp-default
ocfs2-kmp-default
gfs2-kmp-default-debuginfo
ocfs2-kmp-default-debuginfo
gfs2-kmp-default
dlm-kmp-default
cluster-md-kmp-default
dlm-kmp-default-debuginfo
cluster-md-kmp-default-debuginfo
kernel-default-base
kernel-docs
linux (Ubuntu package)
linux-fips (Ubuntu package)
linux-hwe-6.8 (Ubuntu package)
linux-ibm (Ubuntu package)
linux-oracle-6.8 (Ubuntu package)
linux-nvidia (Ubuntu package)
linux-aws-6.8 (Ubuntu package)
linux-aws (Ubuntu package)
linux-azure-fde (Ubuntu package)
linux-azure-fde-6.8 (Ubuntu package)
linux-azure (Ubuntu package)
linux-azure-fips (Ubuntu package)
linux-gcp-fips (Ubuntu package)
linux-raspi (Ubuntu package)

How to mitigate CVE-2026-46063

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
kernel-livepatch-6_4_0-150700_7_62-rt - update to 1-150700.1.3.1
kernel-livepatch-SLE15-SP7-RT_Update_17-debugsource - update to 1-150700.1.3.1
kernel-livepatch-6_4_0-150700_7_62-rt-debuginfo - update to 1-150700.1.3.1
kernel-livepatch-6_4_0-150700_53_66-default - update to 1-150700.15.3.1
kernel-livepatch-SLE15-SP7_Update_18-debugsource - update to 1-150700.15.3.1
kernel-livepatch-6_4_0-150700_53_66-default-debuginfo - update to 1-150700.15.3.1
kernel-kvmsmall-debuginfo - update to 6.4.0-49.1
kernel-rt-devel - addressed in versions 6.4.0-49.1, 6.4.0-150700.7.62.1
kernel-source - addressed in versions 6.4.0-49.1, 6.4.0-150700.53.66.1
kernel-macros - addressed in versions 6.4.0-49.1, 6.4.0-150700.53.66.1
kernel-devel - addressed in versions 6.4.0-49.1, 6.4.0-150700.53.66.1
kernel-default-livepatch - addressed in versions 6.4.0-49.1, 6.4.0-150700.53.66.1
kernel-default-debuginfo - addressed in versions 6.4.0-49.1, 6.4.0-150700.53.66.1
kernel-default-debugsource - addressed in versions 6.4.0-49.1, 6.4.0-150700.53.66.1
kernel-kvmsmall - update to 6.4.0-49.1
kernel-default - addressed in versions 6.4.0-49.1, 6.4.0-150700.53.66.1
kernel-rt-devel-debuginfo - addressed in versions 6.4.0-49.1, 6.4.0-150700.7.62.1
kernel-rt-debugsource - addressed in versions 6.4.0-49.1, 6.4.0-150700.7.62.1
kernel-rt - addressed in versions 6.4.0-49.1, 6.4.0-150700.7.62.1
kernel-default-devel-debuginfo - addressed in versions 6.4.0-49.1, 6.4.0-150700.53.66.1
kernel-kvmsmall-debugsource - update to 6.4.0-49.1
kernel-rt-livepatch - update to 6.4.0-49.1
kernel-rt-debuginfo - addressed in versions 6.4.0-49.1, 6.4.0-150700.7.62.1
kernel-source-rt - addressed in versions 6.4.0-49.1, 6.4.0-150700.7.62.1
kernel-devel-rt - addressed in versions 6.4.0-49.1, 6.4.0-150700.7.62.1
kernel-64kb-debugsource - addressed in versions 6.4.0-49.1, 6.4.0-150700.53.66.1
kernel-64kb-devel - addressed in versions 6.4.0-49.1, 6.4.0-150700.53.66.1
kernel-obs-build - addressed in versions 6.4.0-49.1, 6.4.0-150700.53.66.1
kernel-default-devel - addressed in versions 6.4.0-49.1, 6.4.0-150700.53.66.1
kernel-obs-build-debugsource - addressed in versions 6.4.0-49.1, 6.4.0-150700.53.66.1
kernel-syms - addressed in versions 6.4.0-49.1, 6.4.0-150700.53.66.1
kernel-64kb - addressed in versions 6.4.0-49.1, 6.4.0-150700.53.66.1
dlm-kmp-rt - update to 6.4.0-150700.7.62.1
gfs2-kmp-rt-debuginfo - update to 6.4.0-150700.7.62.1
gfs2-kmp-rt - update to 6.4.0-150700.7.62.1
ocfs2-kmp-rt-debuginfo - update to 6.4.0-150700.7.62.1
cluster-md-kmp-rt - update to 6.4.0-150700.7.62.1
kernel-syms-rt - update to 6.4.0-150700.7.62.1
cluster-md-kmp-rt-debuginfo - update to 6.4.0-150700.7.62.1
ocfs2-kmp-rt - update to 6.4.0-150700.7.62.1
dlm-kmp-rt-debuginfo - update to 6.4.0-150700.7.62.1
kernel-64kb-debuginfo - update to 6.4.0-150700.53.66.1
kernel-zfcpdump - update to 6.4.0-150700.53.66.1
kernel-zfcpdump-debugsource - update to 6.4.0-150700.53.66.1
kernel-zfcpdump-debuginfo - update to 6.4.0-150700.53.66.1
kernel-64kb-devel-debuginfo - update to 6.4.0-150700.53.66.1
kernel-azure-devel - update to 6.4.0-150700.53.66.1
kernel-default-livepatch-devel - update to 6.4.0-150700.53.66.1
kernel-azure - update to 6.4.0-150700.53.66.1
kernel-azure-devel-debuginfo - update to 6.4.0-150700.53.66.1
kernel-azure-debugsource - update to 6.4.0-150700.53.66.1
kernel-azure-debuginfo - update to 6.4.0-150700.53.66.1
kernel-default-extra - update to 6.4.0-150700.53.66.1
kernel-default-extra-debuginfo - update to 6.4.0-150700.53.66.1
reiserfs-kmp-default-debuginfo - update to 6.4.0-150700.53.66.1
reiserfs-kmp-default - update to 6.4.0-150700.53.66.1
ocfs2-kmp-default - update to 6.4.0-150700.53.66.1
gfs2-kmp-default-debuginfo - update to 6.4.0-150700.53.66.1
ocfs2-kmp-default-debuginfo - update to 6.4.0-150700.53.66.1
gfs2-kmp-default - update to 6.4.0-150700.53.66.1
dlm-kmp-default - update to 6.4.0-150700.53.66.1
cluster-md-kmp-default - update to 6.4.0-150700.53.66.1
dlm-kmp-default-debuginfo - update to 6.4.0-150700.53.66.1
cluster-md-kmp-default-debuginfo - update to 6.4.0-150700.53.66.1
kernel-default-base - update to 6.4.0-150700.53.66.1.150700.17.39.1
kernel-docs - update to 6.4.0-150700.53.66.2
linux (Ubuntu package) - addressed in versions 6.8.0-136.136, 6.8.0-1046.50, 6.8.0-1059.67, 6.8.0-1064.72, 6.8.0-1064.72~22.04.1, 6.8.1-1056.57, 6.8.1-1056.57~22.04.2, 7.0.0-27.27
linux-fips (Ubuntu package) - addressed in versions 6.8.0-136.136+fips2, 6.8.0-136.136.2, 6.8.0-136.136.2~22.04.1, 6.8.0-1058.61
linux-hwe-6.8 (Ubuntu package) - update to 6.8.0-136.136~22.04.1
linux-ibm (Ubuntu package) - addressed in versions 6.8.0-1030.31, 6.8.0-1033.34, 6.8.0-1061.62, 6.8.0-1061.62~22.04.1
linux-oracle-6.8 (Ubuntu package) - update to 6.8.0-1058.61~22.04.1
linux-nvidia (Ubuntu package) - addressed in versions 6.8.0-1059.62, 6.8.0-1059.62.1, 6.8.0-1059.62~22.04.1, 7.0.0-1013.13
linux-aws-6.8 (Ubuntu package) - addressed in versions 6.8.0-1061.64+fips1, 6.8.0-1061.64~22.04.1
linux-aws (Ubuntu package) - update to 6.8.0-1061.64+1
linux-azure-fde (Ubuntu package) - update to 6.8.0-1062.69
linux-azure-fde-6.8 (Ubuntu package) - update to 6.8.0-1062.69~22.04.1
linux-azure (Ubuntu package) - addressed in versions 6.8.0-1063.71, 6.8.0-1063.71~22.04.1, 7.0.0-1009.9, 7.0.0-1010.10
linux-azure-fips (Ubuntu package) - update to 6.8.0-1063.71+fips2
linux-gcp-fips (Ubuntu package) - update to 6.8.0-1064.72+fips1
linux-raspi (Ubuntu package) - update to 7.0.0-1014.14

External References

Related Security Bulletins