Out-of-bounds read in Linux kernel - CVE-2026-64018

 

Out-of-bounds read in Linux kernel - CVE-2026-64018

Published: July 20, 2026


Vulnerability identifier: #VU138632
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-2026-64018
CWE-ID: CWE-125
Exploitation vector: Local access
Exploit availability: No public exploit available

Vulnerability details

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

The vulnerability exists due to an out-of-bounds read in mana_hwc_rx_event_handler() when processing hardware-modifiable WQE contents from DMA-coherent memory. A local attacker can modify the derived rx_req_idx value to cause a denial of service.

In confidential VMs such as SEV-SNP and TDX, the affected DMA-coherent memory is shared unencrypted and hardware can modify WQE contents at any time.


Affected software

Linux kernel
SUSE Linux Enterprise Server 15 SP6
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
Red Hat Enterprise Linux for Real Time
Red Hat Enterprise Linux for Real Time for NFV
Red Hat Enterprise Linux for x86_64
Red Hat Enterprise Linux for IBM z Systems
Red Hat Enterprise Linux for Power, little endian
Red Hat Enterprise Linux for ARM 64
Red Hat CodeReady Linux Builder for x86_64
Red Hat CodeReady Linux Builder for Power, little endian
Red Hat CodeReady Linux Builder for ARM 64
SUSE Linux Enterprise Live Patching
Legacy Module
Development Tools Module
Public Cloud Module
Basesystem Module
openSUSE Leap
Ubuntu
kernel-livepatch-6_4_0-150600_23_135-default
kernel-livepatch-6_4_0-150600_23_135-default-debuginfo
kernel-livepatch-SLE15-SP6_Update_31-debugsource
kernel-livepatch-SLE15-SP7_Update_21-debugsource
kernel-livepatch-6_4_0-150700_53_81-default-debuginfo
kernel-livepatch-6_4_0-150700_53_81-default
kernel (Red Hat package)
kernel-rt (Red Hat package)
linux (Ubuntu package)
linux-aws (Ubuntu package)
linux-nvidia-tegra (Ubuntu package)
linux-nvidia-tegra-5.15 (Ubuntu package)
linux-intel-iot-realtime (Ubuntu package)
linux-raspi (Ubuntu package)
linux-intel-iotg (Ubuntu package)
linux-azure (Ubuntu package)
linux-azure-5.15 (Ubuntu package)
linux-gcp-5.15 (Ubuntu package)
linux-azure-fips (Ubuntu package)
linux-azure-fde (Ubuntu package)
kernel-default-livepatch
kernel-devel
kernel-default-livepatch-devel
kernel-docs
reiserfs-kmp-default
reiserfs-kmp-64kb
kernel-64kb-devel-debuginfo
gfs2-kmp-64kb
kselftests-kmp-64kb-debuginfo
kernel-64kb-debuginfo
dlm-kmp-64kb-debuginfo
ocfs2-kmp-64kb-debuginfo
dlm-kmp-64kb
reiserfs-kmp-64kb-debuginfo
kernel-64kb-extra
dlm-kmp-default
cluster-md-kmp-default-debuginfo
ocfs2-kmp-default
gfs2-kmp-default
kernel-obs-build-debugsource
reiserfs-kmp-default-debuginfo
ocfs2-kmp-default-debuginfo
kernel-obs-build
kernel-default-debugsource
kernel-default-devel-debuginfo
dlm-kmp-default-debuginfo
kernel-default-debuginfo
cluster-md-kmp-default
gfs2-kmp-default-debuginfo
kernel-default-devel
kernel-syms
kernel-default
kernel-source
kernel-macros
kernel-kvmsmall-devel
kernel-debug-debugsource
kernel-debug-devel
kernel-debug-debuginfo
kernel-kvmsmall-vdso-debuginfo
kernel-debug-vdso-debuginfo
kernel-kvmsmall-vdso
kernel-default-vdso
kernel-default-vdso-debuginfo
kernel-debug-vdso
kernel-64kb-extra-debuginfo
kernel-kvmsmall-debugsource
kernel-kvmsmall-devel-debuginfo
kernel-kvmsmall-debuginfo
kernel-docs-html
kernel-source-vanilla
kernel-kvmsmall
kernel-zfcpdump
kernel-zfcpdump-debuginfo
kernel-zfcpdump-debugsource
kselftests-kmp-default
kselftests-kmp-64kb
cluster-md-kmp-64kb
ocfs2-kmp-64kb
kernel-64kb-optional-debuginfo
kernel-64kb-devel
gfs2-kmp-64kb-debuginfo
kernel-64kb-optional
kernel-64kb-debugsource
kernel-debug-devel-debuginfo
kernel-default-optional
kernel-default-extra
kselftests-kmp-default-debuginfo
kernel-default-optional-debuginfo
kernel-obs-qa
kernel-default-extra-debuginfo
kernel-64kb
kernel-debug
cluster-md-kmp-64kb-debuginfo
kernel-default-base-rebuild
kernel-default-base
kernel-azure-devel-debuginfo
kernel-azure-debuginfo
kernel-azure-debugsource
kernel-azure-devel
kernel-azure
linux-lowlatency (Ubuntu package)
linux-gcp-6.8 (Ubuntu package)
linux-oracle (Ubuntu package)
linux-azure-fde-6.8 (Ubuntu package)
linux-aws-fips (Ubuntu package)
linux-raspi-realtime (Ubuntu package)
linux-azure-fde-6.17 (Ubuntu package)
linux-azure-6.17 (Ubuntu package)
linux-ibm (Ubuntu package)
linux-gcp-7.0 (Ubuntu package)
linux-oracle-7.0 (Ubuntu package)
linux-azure-7.0 (Ubuntu package)
linux-nvidia (Ubuntu package)
linux-nvidia-bos (Ubuntu package)

How to mitigate CVE-2026-64018

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
kernel-livepatch-6_4_0-150600_23_135-default - update to 1-150600.13.3.4
kernel-livepatch-6_4_0-150600_23_135-default-debuginfo - update to 1-150600.13.3.4
kernel-livepatch-SLE15-SP6_Update_31-debugsource - update to 1-150600.13.3.4
kernel-livepatch-SLE15-SP7_Update_21-debugsource - update to 1-150700.15.3.1
kernel-livepatch-6_4_0-150700_53_81-default-debuginfo - update to 1-150700.15.3.1
kernel-livepatch-6_4_0-150700_53_81-default - update to 1-150700.15.3.1
kernel (Red Hat package) - addressed in versions 4.18.0-553.159.1.el8_10, 6.12.0-211.50.1.el10_2
kernel-rt (Red Hat package) - update to 4.18.0-553.159.1.rt7.500.el8_10
linux (Ubuntu package) - addressed in versions 5.15.0.184.155, 5.15.0-184.194, 5.15.0-184.194~20.04.1, 5.15.0.186.166, 5.15.0-186.196, 5.15.0-186.196~20.04.1, 5.15.0.1075.78, 5.15.0-1075.79, 5.15.0.1095.94, 5.15.0-1095.103, 5.15.0.1104.100, 5.15.0-1104.109, 5.15.0.1108.107, 5.15.0-1108.114, 5.15.0.1111.115, 5.15.0-1111.120+fips1, 5.15.0.1112.102, 5.15.0.1112.109, 5.15.0-1112.122, 5.15.0-1112.122+fips1, 6.8.0-139.139+fips1, 6.8.0-1049.53, 6.8.0-1062.65+fips1, 6.8.0-1062.65.1, 6.8.0-1062.65~22.04.1, 6.8.0-1062.70, 6.8.0-1064.68, 6.8.0-1067.75, 6.8.0-1067.75+fips1, 6.8.1-1059.60, 6.8.1-1059.60~22.04.1
linux-aws (Ubuntu package) - addressed in versions 5.15.0.186.109, 5.15.0-186.196+fips1, 5.15.0.1106.103, 5.15.0-1106.110, 5.15.0.1107.107, 5.15.0-1107.108, 5.15.0.1112.108, 5.15.0.1112.115, 5.15.0-1112.119, 5.15.0-1112.119+fips1, 5.15.0-1112.119~20.04.1, 6.8.0-1064.67~22.04.1, 7.0.0-1009.9, 7.0.0-1015.15
linux-nvidia-tegra (Ubuntu package) - addressed in versions 5.15.0-1053.53, 5.15.0.1053.55, 5.15.0.1064.64, 5.15.0-1064.66, 6.8.0-1035.38
linux-nvidia-tegra-5.15 (Ubuntu package) - update to 5.15.0-1064.66~20.04.1
linux-intel-iot-realtime (Ubuntu package) - addressed in versions 5.15.0-1104.106, 5.15.0.1104.108, 5.15.0-1107.113~20.04.1
linux-raspi (Ubuntu package) - addressed in versions 5.15.0.1106.104, 5.15.0-1106.109
linux-intel-iotg (Ubuntu package) - addressed in versions 5.15.0.1107.106, 5.15.0-1107.113
linux-azure (Ubuntu package) - addressed in versions 5.15.0.1109.105, 5.15.0-1109.115, 5.15.0.1117.115, 5.15.0-1117.126, 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-5.15 (Ubuntu package) - addressed in versions 5.15.0-1109.115~20.04.1, 5.15.0-1117.126~20.04.1, 5.15.0-1117.126~20.04.2
linux-gcp-5.15 (Ubuntu package) - update to 5.15.0-1112.122~20.04.1
linux-azure-fips (Ubuntu package) - addressed in versions 5.15.0.1117.102, 5.15.0-1117.126+fips1, 6.8.0-1063.71+fips2
linux-azure-fde (Ubuntu package) - addressed in versions 5.15.0-1117.126, 6.8.0-1062.69
kernel-default-livepatch - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-devel - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-default-livepatch-devel - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-docs - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
reiserfs-kmp-default - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
reiserfs-kmp-64kb - update to 6.4.0-150600.23.135.1
kernel-64kb-devel-debuginfo - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
gfs2-kmp-64kb - update to 6.4.0-150600.23.135.1
kselftests-kmp-64kb-debuginfo - update to 6.4.0-150600.23.135.1
kernel-64kb-debuginfo - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
dlm-kmp-64kb-debuginfo - update to 6.4.0-150600.23.135.1
ocfs2-kmp-64kb-debuginfo - update to 6.4.0-150600.23.135.1
dlm-kmp-64kb - update to 6.4.0-150600.23.135.1
reiserfs-kmp-64kb-debuginfo - update to 6.4.0-150600.23.135.1
kernel-64kb-extra - update to 6.4.0-150600.23.135.1
dlm-kmp-default - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
cluster-md-kmp-default-debuginfo - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
ocfs2-kmp-default - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
gfs2-kmp-default - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-obs-build-debugsource - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
reiserfs-kmp-default-debuginfo - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
ocfs2-kmp-default-debuginfo - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-obs-build - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-default-debugsource - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-default-devel-debuginfo - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
dlm-kmp-default-debuginfo - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-default-debuginfo - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
cluster-md-kmp-default - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
gfs2-kmp-default-debuginfo - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-default-devel - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-syms - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-default - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-source - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-macros - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-kvmsmall-devel - update to 6.4.0-150600.23.135.1
kernel-debug-debugsource - update to 6.4.0-150600.23.135.1
kernel-debug-devel - update to 6.4.0-150600.23.135.1
kernel-debug-debuginfo - update to 6.4.0-150600.23.135.1
kernel-kvmsmall-vdso-debuginfo - update to 6.4.0-150600.23.135.1
kernel-debug-vdso-debuginfo - update to 6.4.0-150600.23.135.1
kernel-kvmsmall-vdso - update to 6.4.0-150600.23.135.1
kernel-default-vdso - update to 6.4.0-150600.23.135.1
kernel-default-vdso-debuginfo - update to 6.4.0-150600.23.135.1
kernel-debug-vdso - update to 6.4.0-150600.23.135.1
kernel-64kb-extra-debuginfo - update to 6.4.0-150600.23.135.1
kernel-kvmsmall-debugsource - update to 6.4.0-150600.23.135.1
kernel-kvmsmall-devel-debuginfo - update to 6.4.0-150600.23.135.1
kernel-kvmsmall-debuginfo - update to 6.4.0-150600.23.135.1
kernel-docs-html - update to 6.4.0-150600.23.135.1
kernel-source-vanilla - update to 6.4.0-150600.23.135.1
kernel-kvmsmall - update to 6.4.0-150600.23.135.1
kernel-zfcpdump - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-zfcpdump-debuginfo - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-zfcpdump-debugsource - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kselftests-kmp-default - update to 6.4.0-150600.23.135.1
kselftests-kmp-64kb - update to 6.4.0-150600.23.135.1
cluster-md-kmp-64kb - update to 6.4.0-150600.23.135.1
ocfs2-kmp-64kb - update to 6.4.0-150600.23.135.1
kernel-64kb-optional-debuginfo - update to 6.4.0-150600.23.135.1
kernel-64kb-devel - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
gfs2-kmp-64kb-debuginfo - update to 6.4.0-150600.23.135.1
kernel-64kb-optional - update to 6.4.0-150600.23.135.1
kernel-64kb-debugsource - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-debug-devel-debuginfo - update to 6.4.0-150600.23.135.1
kernel-default-optional - update to 6.4.0-150600.23.135.1
kernel-default-extra - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kselftests-kmp-default-debuginfo - update to 6.4.0-150600.23.135.1
kernel-default-optional-debuginfo - update to 6.4.0-150600.23.135.1
kernel-obs-qa - update to 6.4.0-150600.23.135.1
kernel-default-extra-debuginfo - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-64kb - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-debug - update to 6.4.0-150600.23.135.1
cluster-md-kmp-64kb-debuginfo - update to 6.4.0-150600.23.135.1
kernel-default-base-rebuild - update to 6.4.0-150600.23.135.1.150600.12.62.4
kernel-default-base - addressed in versions 6.4.0-150600.23.135.1.150600.12.62.4, 6.4.0-150700.53.81.1.150700.17.45.1
kernel-azure-devel-debuginfo - update to 6.4.0-150700.53.81.1
kernel-azure-debuginfo - update to 6.4.0-150700.53.81.1
kernel-azure-debugsource - update to 6.4.0-150700.53.81.1
kernel-azure-devel - update to 6.4.0-150700.53.81.1
kernel-azure - update to 6.4.0-150700.53.81.1
linux-lowlatency (Ubuntu package) - addressed in versions 6.8.0-139.139.1, 6.8.0-139.139.1~22.04.1
linux-gcp-6.8 (Ubuntu package) - addressed in versions 6.8.0-1036.37, 6.8.0-1064.65, 6.8.0-1067.75~22.04.1
linux-oracle (Ubuntu package) - addressed in versions 6.8.0-1061.64, 6.8.0-1061.64~22.04.1
linux-azure-fde-6.8 (Ubuntu package) - update to 6.8.0-1062.69~22.04.1
linux-aws-fips (Ubuntu package) - update to 6.8.0-1064.67+fips1
linux-raspi-realtime (Ubuntu package) - update to 6.8.0-2053.55
linux-azure-fde-6.17 (Ubuntu package) - update to 6.17.0-1018.18~24.04.1
linux-azure-6.17 (Ubuntu package) - update to 6.17.0-1021.21~24.04.1
linux-ibm (Ubuntu package) - addressed in versions 7.0.0-1008.8, 7.0.0-1010.10
linux-gcp-7.0 (Ubuntu package) - update to 7.0.0-1011.11~24.04.1
linux-oracle-7.0 (Ubuntu package) - update to 7.0.0-1011.11~24.04.1
linux-azure-7.0 (Ubuntu package) - update to 7.0.0-1014.14~24.04.1
linux-nvidia (Ubuntu package) - addressed in versions 7.0.0-1016.16, 7.0.0-1016.16~24.04.1
linux-nvidia-bos (Ubuntu package) - update to 7.0.0-2016.16

External References

Related Security Bulletins